Bone Health in Children and Adolescents with Juvenile Idiopathic Arthritis and Solid Organ Transplant

Osteoporosis is a skeletal disorder characterized by compromised bone strength that predisposes to increased fracture risk. Childhood and adolescence are critical periods for bone mass gain. Peak bone mass is mostly acquired by the age of 18 years and is an important determinant of adult bone health and lifetime risk for fractures. Medications, especially glucocorticoids (GCs), chronic inflammation, decreased physical activity, hormonal deficiencies, delayed puberty, and poor nutrition may predispose children and adolescents with a chronic disease to impaired bone health. In this work, we studied overall bone health, the incidence and prevalence of fractures in children and adolescents who were treated for juvenile idiopathic arthritis (JIA) or had undergone solid organ transplantation. The first study cohort included 62 patients diagnosed with JIA and treated with GCs. The epidemiology of fractures after transplantation was investigated in 196 patients and a more detailed analysis of bone health determinants was performed on 40 liver (LTx) and 106 renal (RTx) transplantation patients. Bone mineral density (BMD) and vertebral morphology were assessed by dual-energy x-ray absorptiometry. Standard radiographs were obtained to detect vertebral fractures and to determine bone age; BMD values were adjusted for skeletal maturity. Our study showed that median BMD values were subnormal in all patient cohorts. The values were highest in patients with JIA and lowest in patients with LTx. Age at transplantation influenced BMD values in LTx but not RTx patients; BMD values were higher in patients who had LTx before the age of two years. BMD was lowest during the immediate posttransplantation years and increased subnormally during puberty. Delayed skeletal maturation was common in all patient groups. The prevalence of vertebral fractures ranged from 10% to 19% in the cohorts. Most of the fractures were asymptomatic and diagnosed only at screening. Vertebral fractures were most common in LTx patients. Vitamin D deficiency was common in all patient groups, and only 3% of patients with JIA and 25% of transplantation patients were considered to have adequate serum vitamin D levels. The total cumulative weight-adjusted dose of GC was not associated with BMD values in JIA or LTx patients. The combination of female gender and age over 15 years, parathyroid hormone concentration over 100 ng/L, and cumulative weight-adjusted methylprednisolone dose over 150 mg/kg during the three preceding years were found to be important predictors for low lumbar spine BMD in RTx patients. Based on the high prevalence of osteoporosis in the study cohorts more efforts should be put to prevention and early diagnosis of osteoporosis in these pediatric patients.

Pitfalls in the Treatment of Persons with Dementia

Pitfalls in the treatment of persons with dementia Persons with dementia require high-quality health care, rehabilitation and sufficient social services to support their autonomy and to postpone permanent institutionalization. This study sought to investigate possible pitfalls in the care of patients with dementia: hip fracture rehabilitation, use of inappropriate or antipsychotic medication, social and medicolegal services offered to dementia caregiving families. Three different Finnish samples were used from years 1999-2005, mean age 78 to 86 years. After hip fracture operation, the weight-bearing restriction especially in group of patients with dementia, was associated with a longer rehabilitation period (73.5 days vs. 45.5 days, p=0.03) and the inability to learn to walk after six weeks (p<0.001). Almost half (44%) of the pre-surgery home-dwellers with dementia in our sample required permanent hospitalization after hip fracture. Potentially inappropriate medication was used among 36.2% of nursing home and hospital patients. The most common PIDs in Finland were temazepam over 15 mg/day, oxybutynin, and dipyridamole. However, PID use failed to predict mortality or the use of health services. Nearly half (48.4%) of the nursing home and hospital patients with dementia used antipsychotic medication. The two-year mortality did not differ among the users of conventional or atypical antipsychotics or the non-users (45.3% vs.32.1% vs.49.6%, p=0.195). The mean number of hospital admissions was highest among non-users (p=0.029). A high number of medications (HR 1.12, p<0.001) and the use of physical restraints (HR 1.72, p=0.034) predicted higher mortality at two years, while the use of atypical antipsychotics (HR 0.49, p=0.047) showed a protective effect, if any. The services most often offered to caregiving families of persons with Alzheimer s disease (AD) included financial support from the community (36%), technical devices (33%), physiotherapy (32%), and respite care in nursing homes (31%). Those services most often needed included physiotherapy for the spouse with dementia (56%), financial support (50%), house cleaning (41%), and home respite (40%). Only a third of the caregivers were satisfied with these services, and 69% felt unable to influence the range of services offered. The use of legal guardians was quite rare (only 4.3%), while the use of financial powers of attorney was 37.8%. Almost half (47.9%) of the couples expressed an unmet need for discussion with their doctor about medico-legal issues, while only 9.9% stated that their doctor had informed them of such matters. Although we already have many practical methods to develop the medical and social care of persons with AD, these patients and their families require better planning and tailoring of such services. In this way, society could offer these elderly persons better quality of life while economizing on its financial resources. This study was supported by Social Insurance Institution of Finland and part of it made in cooperation with the The Central Union of the Welfare for the Aged, Finland.

Sentinel lymph node biopsy as a diagnostic tool in the treatment of breast cancer

The purpose of this study was to evaluate the use of sentinel node biopsy (SNB) in the axillary nodal staging in breast cancer. A special interest was in sentinel node (SN) visualization, intraoperative detection of SN metastases, the feasibility of SNB in patients with pure tubular carcinoma (PTC) and in those with ductal carcinoma in situ (DCIS) in core needle biopsy (CNB) and additionally in the detection of axillary recurrences after tumour negative SNB. Patients and methods. 1580 clinically stage T1-T2 node-negative breast cancer patients, who underwent lymphoscintigraphy (LS), SNB and breast surgery between June 2000 - 2004 at the Breast Surgery Unit. The CNB samples were obtained from women, who participated the biennial, population based mammography screening at the Mammography Screening Centre of Helsinki 2001 - 2004.In the follow- up, a cohort of 205 patients who avoided AC due to negative SNB findings were evaluated using ultrasonography one and three years after breast surgery. Results. The visualization rate of axillary SNs was not enhanced by adjusting radioisotope doses according to BMI. The sensitivity of the intraoperative diagnosis of SN metastases of invasive lobular carcinoma (ILC) was higher, 87%, with rapid, intraoperative immunohistochemistry (IHC) group compared to 66% without it. The prevalence of tumour positive SN findings was 27% in the 33 patients with breast tumours diagnosed as PTC. The median histological tumour size was similar in patients with or without axillary metastases. After the histopathological review, six out of 27 patients with true PTC had axillary metastases, with no significant change in the risk factors for axillary metastases. Of the 67 patients with DCIS in the preoperative percutaneous biopsy specimen , 30% had invasion in the surgical specimen. The strongest predictive factor for invasion was the visibility of the lesion in ultrasound. In the three year follow-up, axillary recurrence was found in only two (0.5%) of the total of 383 ultrasound examinations performed during the study, and only one of the 369 examinations revealed cancer. None of the ultrasound examinations were false positive, and no study participant was subjected to unnecessary surgery due to ultrasound monitoring. Conclusions. Adjusting the dose of the radioactive tracer according to patient BMI does not increase the visualization rate of SNs. The intraoperative diagnosis of SN metastases is enhanced by rapid IHC particularly in patients with ILC. SNB seems to be a feasible method for axillary staging of pure tubular carcinoma in patients with a low prevalence of axillary metatastases. SNB also appears to be a sensible method in patients undergoing mastectomy due to DCIS in CNB. It also seems useful in patients with lesions visible in breast US. During follow-up, routine monitoring of the ipsilateral axilla using US is not worthwhile among breast cancer patients who avoided AC due to negative SN findings.

Assessment of Risk for Type 1 Diabetes in Children of Affected Families and in the General Population : Role of Immunological and Metabolic Markers

Background and aims. Type 1 diabetes (T1D), an autoimmune disease in which the insulin producing beta cells are gradually destroyed, is preceded by a prodromal phase characterized by appearance of diabetes-associated autoantibodies in circulation. Both the timing of the appearance of autoantibodies and their quality have been used in the prediction of T1D among first-degree relatives of diabetic patients (FDRs). So far, no general strategies for identifying individuals at increased disease risk in the general population have been established, although the majority of new cases originate in this population. The current work aimed at assessing the predictive role of diabetes-associated immunologic and metabolic risk factors in the general population, and comparing these factors with data obtained from studies on FDRs. Subjects and methods. Study subjects in the current work were subcohorts of participants of the Childhood Diabetes in Finland Study (DiMe; n=755), the Cardiovascular Risk in Young Finns Study (LASERI; n=3475), and the Finnish Type 1 Diabetes Prediction and Prevention Study (DIPP) Study subjects (n=7410). These children were observed for signs of beta-cell autoimmunity and progression to T1D, and the results obtained were compared between the FDRs and the general population cohorts. --- Results and conclusions. By combining HLA and autoantibody screening, T1D risks similar to those reported for autoantibody-positive FDRs are observed in the pediatric general population. Progression rate to T1D is high in genetically susceptible children with persistent multipositivity. Measurement of IAA affinity failed in stratifying the risk assessment in young IAA-positive children with HLA-conferred disease susceptibility, among whom affinity of IAA did not increase during the prediabetic period. Young age at seroconversion, increased weight-for-height, decreased early insulin response, and increased IAA and IA-2A levels predict T1D in young children with genetic disease susceptibility and signs of advanced beta-cell autoimmunity. Since the incidence of T1D continues to increase, efforts aimed at preventing T1D are important, and reliable disease prediction is needed both for intervention trials and for effective and safe preventive therapies in the future. Our observations confirmed that combined HLA-based screening and regular autoantibody measurements reveal similar disease risks in pediatric general population as those seen in prediabetic FDRs, and that risk assessment can be stratified further by studying glucose metabolism of prediabetic subjects. As these screening efforts are feasible in practice, the knowledge now obtained can be exploited while designing intervention trials aimed at secondary prevention of T1D.

Psychiatric disturbances in children with intellectual disability : Prevalence, risk factors and assessment

Children with intellectual disability are at increased risk for emotional and behavioural problems, but many of these disturbances fail to be diagnosed. Structured checklists have been used to supplement the psychiatric assessment of children without intellectual disability, but for children with intellectual disability, only a few checklists are available. The aim of the study was to investigate psychiatric disturbances among children with intellectual disability: the prevalence, types and risk factors of psychiatric disturbances as well as the applicability of the Finnish translations of the Developmental Behaviour Checklist (DBC-P) and the Child Behavior Checklist (CBCL) in the assessment of psychopathology. The subjects comprised 155 children with intellectual disability, and data were obtained from case records and five questionnaires completed by the parents or other carers of the child. According to case records, a psychiatric disorder had previously been diagnosed in 11% of the children. Upon careful re-examination of case records, the total proportion of children with a psychiatric disorder increased to 33%. According to checklists, the frequency of probable psychiatric disorder was 34% by the DBC-P, and 43% by the CBCL. The most common diagnoses were pervasive developmental disorders and hyperkinetic disorders. The results support previous findings that compared with children without intellectual disability, the risk of psychiatric disturbances is 2-3-fold in children with intellectual disability. The risk of psychopathology was most significantly increased by moderate intellectual disability and low socio-economic status, and decreased by adaptive behaviour, language development, and socialisation as well as living with both biological parents. The results of the study suggest that both the DBC-P and the CBCL can be used to discriminate between children with intellectual disability with and without emotional or psychiatric disturbance. The DBC-P is suitable for children with any degree of intellectual disability, and the CBCL is suitable at least for children with mild intellectual disability. Because the problems of children with intellectual disability differ somewhat from those of children without intellectual disability, checklists designed specifically for children with intellectual disability are needed.

Vertigo in children

Vertigo in children is more common than previously thought. However, only a small fraction of affected children meet a physician. The reason for this may be the benign course of vertigo in children. Most childhood vertigo is self-limiting, and the provoking factor can often be identified. The differential diagnostic process in children with vertigo is extensive and quite challenging even for otologists and child neurologists, who are the key persons involved in treating vertiginous children. The cause of vertigo can vary from orthostatic hypotension to a brain tumor, and thus, a structured approach is essential in avoiding unnecessary examinations and achieving a diagnosis. Common forms of vertigo in children are otitis media-related dizziness, benign paroxysmal vertigo of childhood, migraine-associated dizziness, and vestibular neuronitis. Orthostatic hypotension, which is not a true vertigo, is the predominant type of dizziness in children. Vertigo is often divided according to origin into peripheral and central types. An otologist is familiar with peripheral causes, while a neurologist treats central causes. Close cooperation between different specialists is essential. Sometimes consultation with a psy-chiatrist or an ophthalmologist can lead to the correct diagnosis. The purpose of this study was to evaluate the prevalence and clinical characteristics of vertigo in children. We prospectively collected general population-based data from three schools and one child wel-fare clinic located close to Helsinki University Central Hospital (HUCH). A simple questionnaire with mostly closed questions was given to 300 consecutive children visiting the welfare clinic. At the schools, entire classes that fit the desired age groups received the questionnaire. Of the 1050 children who received the questionnaire, 938 (473 girls, 465 boys) returned it, the response rate thus being 89% (I). In Study II, we evaluated the 24 vertiginous children (15 girls, 9 boys) with true vertigo and 12 healthy age- and gender-matched controls. A detailed medical history was obtained using a structured approach, and an otoneurologic examination, including audiogram, electronystagmography, and tympanometry, was performed at the HUCH ear, nose, and throat clinic for cooperative subjects. In Study III, we reviewed and evaluated the medical records of 119 children (63 girls, 56 boys) aged 0-17 years who had visited the ear, nose, and throat clinic with a primary complaint of vertigo in 2000-2004. We also wanted information about indications for imaging of the head in vertiginous children. To this end, we reviewed the medical records of 978 children who had undergone imaging of the head for various indications. Of these, 87 children aged 0-16 years were imaged because of vertigo. Subjects of interest were the 23 vertiginous children with an acute deviant finding in magnetic resonance images or com-puterized tomography (IV). Our results indicate that vertigo and other balance problems in children are quite common. Of the HUCH area population, 8% of the children had sometimes experienced vertigo, dizziness, or balance problems. Of these 23% had vertigo sufficiently severe to stop their activity (I). The structured data collection approach eased the evaluation of vertiginous children. More headaches and head traumas were observed in vertiginous children than in healthy controls (II). The most common diagnoses of ear, nose, and throat clinic patients within the five-year period were benign paroxysmal vertigo of child-hood, migraine-associated dizziness, vestibular neuronitis, and otitis media-related vertigo. Valuable diagnostic tools in the diagnostic process were patient history and otoneurologic examinations, includ-ing audiogram, electronystagmography, and tympanometry (III). If the vertiginous child had neurologi-cal deficits, persistent headache, or preceding head trauma, imaging of the head was indicated (IV).

Cyclosporine A in the treatment of Interstitial Cystitis

Painful bladder syndrome/interstitial cystitis (PBS/IC) is a chronic urinary bladder disorder of unknown etiology characterized by symptoms of bladder pain and urinary frequency. PBS/IC is a chronic disease in which drug therapy has not led to significant success over the course of time. If the symptoms of PBS/IC are refractory to standard treatments, a possible cure might demand surgical intervention involving cystectomy. The eventual autoimmune etiology in mind, immunosuppressive drug therapy with cyclosporine A (CyA) was started to patients with refractory PBS/IC. CyA is a potent anti-inflammatory drug, a calcineurin inhibitor which inhibits T lymphocyte IL-2 produc-tion. T cells are present in abundance in inflammation of the bladder in PBS/IC. On the basis of a pilot, short-term study with CyA on PBS/IC, use of CyA was continued empirically over the long term. We conducted a prospective, randomized, six-month study in 64 patients comparing the effect of CyA with the FDA approved treatment, pentosan polysulfate sodium (PPS). We measured the drug effect on patient s symptoms, the potassium sensitivity test, and on urinary biomarkers. We further tested the impact of CyA, PPS, DMSO and BCG therapy on a health-related quality of life questionnaire and evaluated the response rate to treatment with these therapies. Long-term use of CyA was safe and effective in PBS/IC patients. The good clinical effect matured individually during the years in which CyA was continued. Cessation of medication led to the reappearance of symptoms, and restarting CyA to renewed alleviation, so that CyA was administered as continuous medication. The response rate to CyA increased during the study period, comprising 75% of CyA patients at six months. 19% of patients responded to PPS therapy. Adverse effects were more common in the CyA group, underlining the importance of monitoring the drug safety and appropriate titration of the dose. The potassium sensitivity test is positive in the majority of PBS/IC patients. Successful therapy of PBS/IC can alter nerve sensitivity to external potassium. This effect was seen more often after CyA therapy. Successful treatment of PBS/IC with CyA resulted to decreasing urinary levels of EGF. IL-6 levels in urine were higher among older patient with a longer history of PBS/IC. In these patients, reduced levels of urinary IL-6 were measured after CyA therapy. Patients who experience the best treatment response have improved quality of life according to the post-treatment health-related quality of life (HRQOL) questionnaire. CyA had more impact on the ma-jority of the aspects of QoL than PPS. Despite DMSO therapy being more successful than BCG in the count of responders, DMSO and BCG had equal effects on the HRQOL questionnaire.

The effectiveness of infrainguinal percutaneous transluminal angioplasty in the treatment of critical limb ischaemia

Critical chronic lower limb ischaemia (CLI) is the most severe form of peripheral arterial disease. Even though the treatment of CLI has evolved during the last decade, CLI is still associated with considerable morbidity, mortality and a decreased quality of life, in addition to a large financial impact on society. ---- Bypass surgery has traditionally been considered the approach of choice to treat CLI patients in order to avoid amputation. However, there are increasing data on the efficacy of endovascular revascularization procedures, such as percutaneous transluminal angioplasty (PTA), to achieve good leg salvage rates as well. Data gathered on all the 2,054 CLI patients revascularized at the Helsinki University Central Hospital between 2000 and 2007 were retrospectively analyzed. This patient cohort was used to compare the results of infrainguinal PTA and bypass surgery as well as to investigate predictors of failure after PTA. This study showed that infrainguinal PTA and bypass surgery yielded rather similar results in terms of survival, amputation-free survival and freedom from any re-intervention. When the femoropoliteal segment was treated, leg salvage was significantly better in the bypass surgery group, whereas no significant difference was observed between the two treatment methods when the revascularization extended to the infrapopliteal segment. PTA resulted in a significantly lower freedom from surgical re-interventions when compared to surgical revascularization. In this study the most important predictors of poor outcome after PTA for CLI were cardiac morbidity, nonambulatory status upon hospital arrival, and gangrene as a manifestation of CLI. Thus, when feasible, PTA seems to be a valid alternative for bypass surgery in the treatment of CLI provided that active redo-surgery is utilized. The optimal revascularization strategy should always be sought for each CLI patient individually considering the clinical state of the leg, the occlusive lesions to be treated, co-morbidities, life-expectancy, and the availability of a suitable vein for bypass.

Phonological Mean Length of Utterance as an indicator of typical and impaired phonological development in children acquiring Finnish

The aim of this study was to examine the applicability of the Phonological Mean Length of Utterance (pMLU) method to the data of children acquiring Finnish, for both typically developing children and children with a Specific Language Impairment (SLI). Study I examined typically developing children at the end of the one-word stage (N=17, mean age 1;8), and Study II analysed children s (N=5) productions in a follow-up study with four assessment points (ages 2;0, 2;6, 3;0, 3;6). Study III was carried out in the form of a review article that examined recent research on the phonological development of children acquiring Finnish and compared the results with general trends and cross-linguistic findings in phonological development. Study IV included children with SLI (N=4, mean age 4;10) and age-matched peers. The analyses in Studies I, II and IV were made using the quantitative pMLU method. In the pMLU method, pMLU values are counted for both the words that the children targeted (so-called target words) and the words produced by the children. When the child s average pMLU value was divided with the average target word pMLU value, it is possible to examine that child s accuracy in producing the words with the Whole-Word Proximity (PWP) value. In addition, the number of entirely correctly produced words is counted to obtain the Whole-Word Correctness (PWC) value. Qualitative analyses were carried out in order to examine how the children s phoneme inventories and deficiencies in phonotactics would explain the observed pMLU, PWP and PWC values. The results showed that the pMLU values for children acquiring Finnish were relatively high already at the end of the one-word stage (Study I). The values were found to reflect the characteristics of the ambient language. Typological features that lead to cross-linguistic differences in pMLU values were also observed in the review article (Study III), which noted that in the course of phonological acquisition there are a large number of language-specific phenomena and processes. Study II indicated that overall the children s phonological development during the follow-up period was reflected in the pMLU, PWP and PWC values, although the method showed limitations in detecting qualitative differences between the children. Correct vowels were not scored in the pMLU counts, which led to some misleadingly high pMLU and PWP results: vowel errors were only reflected in the PWC values. Typically developing children in Study II reached the highest possible pMLU results already around age 3;6. At the same time, the differences between the children with SLI and age-matched peers in the pMLU values were very prominent (Study IV). The values for the children with SLI were similar to the ones reported for two-year-old children. Qualitative analyses revealed that the phonologies of the children with SLI largely resembled the ones of younger, typically developing children. However, unusual errors were also witnessed (e.g., vowel errors, omissions of word-initial stops, consonants added to the initial position in words beginning with a vowel). This dissertation provides an application of a new tool for quantitative phonological assessment and analysis in children acquiring Finnish. The preliminary results suggest that, with some modifications, the pMLU method can be used to assess children s phonological development and that it has some advantages compared to the earlier, segment-oriented approaches. Qualitative analyses complemented the pMLU s observations on the children s phonologies. More research is needed in order to verify the levels of the pMLU, PWP and PWC values in children acquiring Finnish.

Snoring and sleep apnea in children

Snoring is a primary and major clinical symptom of upper airway obstruction during sleep. Sleep-disordered breathing ranges from primary snoring to significant partial upper airway obstruction, and obstructive sleep apnea. Adult snoring and obstructive sleep apnea have been extensively studied, whereas less is known about these disorders in children. Snoring and more severe obstructive sleep apnea have been shown to have a harmful effect on the neurobehavioral development of children, but the mechanisms of this effect remains unknown. Furthermore, the correlation of this effect to objective sleep study parameters remains poor. This study evaluated the prevalence of snoring in preschool-aged children in Finland. Host and environmental risk factors, and neurobehavioral and neurocognitive symptoms of children suffering from snoring or obstructive sleep apnea were also investigated. The feasibility of acoustic rhinometry in young children was assessed. The prevalence and risk factors of snoring (I) were evaluated by a questionnaire. The random sample included 2100 children aged 1-6 years living in Helsinki. All 3- to 6-year-old children whose parents reported their child to snore always, often, or sometimes were categorized as snorers, and invited to participate to the clinical study (II-IV). Non-snoring children whose parents were willing to participate in the clinical study were invited to serve as controls. Children underwent a clinical ear-nose-throat examination. Emotional, behavioral, and cognitive performances were evaluated by Child Behavioral Checklist (CBCL), Wechsler Preschool and Primary Scale of Intelligence (WPPSI-R) and NEPSY-A Developmental Neuropsychological Assessment (NEPSY). Nasal volume was measured by acoustic rhinometry, and nasal resistance by rhinomanometry. Lateral and posteroanterior cephalometry were performed. A standard overnight ambulatory polysomnography was performed in the home environment. Twenty-six healthy children were tested in order to assess the feasibility of acoustic rhinometry in young children (V). Snoring was common in children; 6.3% of children snored always or often, whereas 81.3% snored never or occasionally. No differences were apparent between snorers and non-snorers regarding age, or gender. Pediatric snoring was associated with recurrent upper respiratory infections, otitis media, and allergic rhinitis. Exposure to parental tobacco smoke, especially maternal smoking, was more common among snorers. Rhinitis was more common among children who exposured to tobacco smoke. Overnight polysomnography (PSG) was performed on 87 children; 74% showed no signs of significant upper airway obstruction during sleep. Three children had obstructive apnea/hypopnea index (OAHI) greater than 5/h. Age, gender, or a previous adenoidectomy or tonsillectomy did not correlate with OAHI, whereas tonsillar size did correlate with OAHI. Relative body weight and obesity correlated with none of the PSG parameters. In cephalometry, no clear differences or correlations were found in PSG parameters or between snorers and non-snorers. No correlations were observed between acoustic rhinometry, rhinomanometry, and PSG parameters. Psychiatric symptoms were more frequent in the snoring group than in the nonsnoring group. In particular, anxious and depressed symptoms were more prevalent in the snoring group. Snoring children frequently scored lower in language functions. However, PSG parameters correlated poorly with neurocognitive test results in these children. This study and previous studies indicate that snoring without episodes of obstructive apnea or SpO2 desaturations may cause impairment in behavioral and neurocognitive functions. The mechanism of action remains unknown. Exposure to parental tobacco smoke is more common among snorers than non-snorers, emphasizing the importance of a smoke-free environment. Children tolerated acoustic rhinometry measurements well.

Vitamin D deficiency in children with chronic illnesses: Predisposing and protecting factors

This thesis assesses clinical differences in patients with low and high vitamin D levels. The factors analyzed included the underlying disease, body size, age, ethnic background, use of vitamin D supplements and the season when the blood sample was taken. Fifty patients with the lowest and 50 patients with the highest vitamin D concentrations were selected from a cohort of 1351 chronically ill children and adolescents who had had their vitamin D status assessed at Children's Hospital. Protective factors appeared to be the usage of vitamin D supplements and young age, especially age <2 years. Predisposing factors included non-Finnish ethnic background and older age, especially age 12-18 years. High vitamin D values were more prevalent in the summer and autumn and low values in the winter and spring. Patients with non-Finnish background were overrepresented in the low value group. No differences regarding the underlying diseases could be detected. Conclusions: In the Northern latitudes UVB-radiation is insufficient for vitamin D synthesis. Vitamin D recommendations appear to be inadequate to fulfill the needs of chronically ill patients whose requirements for vitamin D are elevated compared to the general population. New guidelines for vitamin D supplementation are needed particularly for those at risk of developing vitamin D deficiency.