Mapping tibiofemoral gonarthrosis: an MRI analysis of non-traumatic knee cartilage defects

OBJECTIVE Arthroscopy is "the gold standard" for the diagnosis of knee cartilage lesions. However, it is invasive and expensive, and displays all the potential complications of an open surgical procedure. Ultra-high-field MRI now offers good opportunities for the indirect assessment of the integrity and structural changes of joint cartilage of the knee. The goal of the present study is to determine the site of early cartilaginous lesions in adults with non-traumatic knee pain. METHODS 3-T MRI examinations of 200 asymptomatic knees with standard and three-dimensional double-echo steady-state (3D-DESS) cartilage-specific sequences were prospectively studied for early degenerative lesions of the tibiofemoral joint. Lesions were classified and mapped using the modified Outerbridge and modified International Cartilage Repair Society classifications. RESULTS A total of 1437 lesions were detected: 56.1% grade I, 33.5% grade II, 7.2% grade III and 3.3% grade IV. Cartographically, grade I lesions were most common in the anteromedial tibial areas; grade II lesions in the anteromedial L5 femoral areas; and grade III in the centromedial M2 femoral areas. CONCLUSION 3-T MRI with standard and 3D-DESS cartilage-specific sequences demonstrated that areas predisposed to early osteoarthritis are the central, lateral and ventromedial tibial plateau, as well as the central and medial femoral condyle. ADVANCES IN KNOWLEDGE In contrast with previous studies reporting early cartilaginous lesions in the medial tibial compartment and/or in the medial femoral condyle, this study demonstrates that, regardless of grade, lesions preferentially occur at the L5 and M4 tibial and L5 and L2 femoral areas of the knee joint.

Regression of coronary atherosclerosis: Current evidence and future perspectives

Coronary atherosclerosis has been considered a chronic disease characterized by ongoing progression in response to systemic risk factors and local pro-atherogenic stimuli. As our understanding of the pathobiological mechanisms implicated in atherogenesis and plaque progression is evolving, effective treatment strategies have been developed that led to substantial reduction of the clinical manifestations and acute complications of coronary atherosclerotic disease. More recently, intracoronary imaging modalities have enabled detailed in vivo quantification and characterization of coronary atherosclerotic plaque, serial evaluation of atherosclerotic changes over time, and assessment of vascular responses to effective anti-atherosclerotic medications. The use of intracoronary imaging modalities has demonstrated that intensive lipid lowering can halt plaque progression and may even result in regression of coronary atheroma when the highest doses of the most potent statins are used. While current evidence indicates the feasibility of atheroma regression and of reversal of presumed high-risk plaque characteristics in response to intensive anti-atherosclerotic therapies, these changes of plaque size and composition are modest and their clinical implications remain largely elusive. Growing interest has focused on achieving more pronounced regression of coronary plaque using novel anti-atherosclerotic medications, and more importantly on elucidating ways toward clinical translation of favorable changes of plaque anatomy into more favorable clinical outcomes for our patients.

Reduced pro-inflammatory profile of γδT cells in pregnant patients with rheumatoid arthritis

BACKGROUND During pregnancy, many patients with rheumatoid arthritis (RA) experience disease improvement, whereas patients with ankylosing spondylitis often suffer from persistent active disease. Here we investigated whether pregnancy-related changes in disease activity were associated with changes in the proportion and function of γδT cells. METHODS The study population comprised 55 patients with RA, 31 patients with ankylosing spondylitis, and 35 healthy controls. Among these participants, 28 RA patients, 21 ankylosing spondylitis patients, and 23 healthy controls were investigated once before conception when possible, at each trimester of pregnancy, and at 8 weeks postpartum. Data were compared with age-matched non-pregnant patients to obtain disease-related background. In all subjects, peripheral Vδ1 and Vδ2 T cells were analyzed for cell frequencies, the activation marker CD69, the cytotoxicity markers NKG2D and NKG2A, and the intracellular cytokines tumor necrosis factor (TNF)α, interferon (IFN)γ, interleukin (IL)-17 and IL-10. RESULTS Pregnant patients showed a decreased Vδ2/Vδ1 ratio in the third trimester, which resulted from a slightly reduced proportion of Vδ2 cells. Changes in RA disease activity during pregnancy and postpartum were not associated with numerical proportions of γδT cells but with changes of the cell activation marker CD69 on Vδ1 and Vδ2 cells. Only RA patients showed reduced proportions of TNFα-positive Vδ1and Vδ2 cells and IFNγ-positive Vδ2 cells at the third trimester of pregnancy, a finding that was not apparent in the entire population of CD3 T cells. The proportions of IL-17-positive γδT cells and IL-10-positive γδT cells did not differ between pregnant and non-pregnant women of the different groups. CONCLUSIONS Changes of disease activity in pregnant RA patients were associated with functional changes in both γδT cell subsets. This reduced pro-inflammatory profile of γδT cells might contribute to the immunomodulation resulting in pregnancy-induced improvement of RA.

Incidence of preeclampsia in pregnant Swiss women.

QUESTION UNDER STUDY The epidemiology of preeclampsia in Switzerland is known only from a retrospective registry study. This analysis aimed to prospectively determine the incidence of preeclampsia in a cohort of pregnant women in Switzerland. METHODS Pregnant women presenting at gestational week 11-14 at their obstetrician's office were consecutively included and prospectively followed-up until the end of pregnancy. Ultrasound characteristics, blood pressure measurements, body mass index, and personal history were recorded. Duration of pregnancy, occurrence of preeclampsia, birth weight and Apgar scores were recorded as outcomes. RESULTS There were 1,300 pregnancies with follow-up available for analysis. Median age was 30 years (interquartile range [IQR] 27-33), median body mass index (BMI) 23.3 kg/m² (IQR 21.2-26.1), median systolic blood pressure 117 mm Hg (IQR 109-126) and median diastolic blood pressure 70 mm Hg (IQR 64-77). A total of 30 women developed preeclampsia, corresponding to an incidence of 2.31% (95% confidence interval [CI] 1.62%-3.28%). Of the women with preeclampsia, 6.66% (95% CI 2.04%-21.42%) had early-onset preeclampsia, 13.33% (95% CI 5.45%-29.83%) progressed to eclampsia, whereas 10% (95% CI 3.63%-28.75%) developed HELLP syndrome (haemolysis, elevated liver enzymes, low platelet count). Nulliparity and prior history of preeclampsia were more frequently seen in pregnancies with preeclampsia than in pregnancies without preeclampsia. BMI, as well as systolic and diastolic blood pressure were higher in pregnancies subsequently developing preeclampsia. CONCLUSION The incidence of preeclampsia in Switzerland is in line with frequencies observed elsewhere in the world. Extrapolation to a national level indicates that about 1,911 (range 1,340-2,713) preeclampsia cases per year can be expected to occur in Switzerland.

Pregnancy Outcomes in Subjects Exposed to Certolizumab Pegol.

OBJECTIVE To provide information on pregnancy outcomes in women receiving certolizumab pegol (CZP). METHODS The UCB Pharma safety database was searched for pregnancies through to September 1, 2014. Reports for maternal and paternal CZP exposure were included and outcomes examined, and data on CZP exposure, pregnancy, comorbidities, and infant events were extracted by 2 independent reviewers. Concomitant medications and disease activity were reviewed for clinical trial patients. RESULTS Of 625 reported pregnancies, 372 (59.5%) had known outcomes. Paternal exposure pregnancies (n = 33) reported 27 live births, 4 miscarriages, 1 induced abortion, and 1 stillbirth. Maternal exposure pregnancies (n = 339) reported 254 live births, 52 miscarriages, 32 induced abortions, and 1 stillbirth. Almost all reported pregnancies had exposure to CZP in the first trimester, when organogenesis takes place, and a third of them continued the drug into the second and/or third trimesters. The most frequent indications for maternal CZP use were Crohn disease (192/339) and rheumatic diseases (118/339). Twelve cases of congenital malformation and a single neonatal death were reported. CONCLUSION Analysis of pregnancy outcomes after exposure to CZP supports previous reports, suggesting a lack of harmful effect of maternal CZP exposure on pregnancy outcomes. However, additional data from a larger number of outcomes after exposure and studies including an unexposed comparison group are required to fully evaluate CZP safety and tolerability in pregnancy.

Dose-dependent effects of experimental infection with the virulent Neospora caninum Nc-Spain7 isolate in a pregnant mouse model.

Pregnant BALB/c mice have been widely used as an in vivo model to study Neospora caninum infection biology and to provide proof-of-concept for assessments of drugs and vaccines against neosporosis. The fact that this model has been used with different isolates of variable virulence, varying infection routes and differing methods to prepare the parasites for infection, has rendered the comparison of results from different laboratories impossible. In most studies, mice were infected with similar number of parasites (2 × 10(6)) as employed in ruminant models (10(7) for cows and 10(6) for sheep), which seems inappropriate considering the enormous differences in the weight of these species. Thus, for achieving meaningful results in vaccination and drug efficacy experiments, a refinement and standardization of this experimental model is necessary. Thus, 2 × 10(6), 10(5), 10(4), 10(3) and 10(2) tachyzoites of the highly virulent and well-characterised Nc-Spain7 isolate were subcutaneously inoculated into mice at day 7 of pregnancy, and clinical outcome, vertical transmission, parasite burden and antibody responses were compared. Dams from all infected groups presented nervous signs and the percentage of surviving pups at day 30 postpartum was surprisingly low (24%) in mice infected with only 10(2) tachyzoites. Importantly, infection with 10(5) tachyzoites resulted in antibody levels, cerebral parasite burden in dams and 100% mortality rate in pups, which was identical to infection with 2 × 10(6) tachyzoites. Considering these results, it is reasonable to lower the challenge dose to 10(5) tachyzoites in further experiments when assessing drugs or vaccine candidates.

Prenatal care: A survey of African American women in Houston

The focus of the study was to identify variables that African American women who delivered at a teaching hospital in Houston, Harris County, Texas, between January 12, 1998 and April 24, 1998 perceived to prevent them from receiving adequate prenatal care. The research was based on Aday and Andersen's Framework for the Study of Access to Medical Care. A self-administered questionnaire, using realized and potential access indicators, was developed and administered to 161 African American patients at the study hospital. ^ The objectives of the study were (1) to describe the demographic characteristics of African American women who delivered at a large urban teaching hospital between January 12, 1998 and April 24, 1998; and to determine the relationships between (2) predisposing factors such as age, race, educational level, marital status, family structure, social support and attitude toward prenatal care and prenatal care utilization; (3) enabling factors such as income, employment, insurance status, transportation, appointment, and regular source of care; (4) need factors such as perceived health status, number of past pregnancies, pregnancy occurrence; and (5) the relative importance of predisposing, enabling and need factors as predictors of utilization of prenatal care. The indicators of prenatal care utilization examined included the trimester in which the women initiated prenatal care, number of visits, and numbers and types of services received during pregnancy. Barriers cited included low income and inadequate insurance coverage, problems of transportation and child care, unawareness of pregnancy, delays in the scheduling of appointments, and having too many other problems. ^ The results of the study have implications for well-defined public health promotion campaigns, social support system enhancement, and appointment scheduling reform with an emphasis on prenatal care. ^

Female-specific regulation of cytochrome P450 3As and their response to xenobiotic stress

Cytochrome P450 3As (CYP3As) are phase I enzymes responsible for metabolizing more than 50% of clinical drugs. Recent studies have revealed that expression of CYP3As is two-fold higher in women than in men leading to a faster metabolic clearance of therapeutic drugs in women. In this study, we analyzed the female specific rat CYP3A isoform, CYP3A9. We evaluated the effects of progesterone and estrogen on CYP3A9 regulation and showed a distinct role for estrogen in mediating female dominance of CYP3A9. We also observed changes in CYP3A9 expression at various stages of pregnancy which correlates well with varying physiological estradiol concentrations. In addition, by the in vitro data shows that estradiol mediated induction can be abrogated with estrogen receptor antagonist ICI182,780. We also identified three novel murine CYP3A isoforms CYP3A13, CYP3A41 and CYP3A44 and characterized their genomic structures and expression profiles. CYP3A41 and CYP3A44 show female specific expression but surprisingly this female dominance is not mediated via estrogen. Control male mice did not exhibit any CYP3A41 mRNA levels but showed minimal levels of CYP3A44. In order to gain insights into the governance ofαthe female specific genes, the hepatic regulation of CYP3A41 and CYP3A44 by the xeno-sensors PXR and CAR was examined. In female mice, pregnenolone-16α-carboxynitrile, suppressed CYP3A41 and CYP3A44 mRNA levels in PXR−/− background whereas dexamethasone-dependent suppression of CYP3A41 was mediated by PXR. In addition, phenobarbital challenge in PXR−/− revealed up-regulation of both CYP3A44, CYP3A41 levels only in males. No role for CAR was seen in the regulation of either CYP3A41 or CYP3A44 gene expression in female mice. Interestingly, PXR and CAR ligands induced male CYP3A44 levels in a receptor dependent fashion. This increase of CYP3A44 transcript in male mice is in contrast to the response seen in female mice, which clearly indicates an additional layer of regulation. Our findings suggest that gender plays a strategic role in directing the CAR/PXR mediated effects of CYP3A44/CYP3A41. This implies that differential regulation of female specific CYP3A isoforms may be the key to explain some of the gender differences observed in clearance of certain therapeutics like antidepressants and analgesics. ^

A constellation of factors associated with premature births among African American women

A cohort, cross-sectional, historical study design was used to study factors related to spontaneous premature birth outcomes among African American women. The cohort consisted of 4,294 mothers drawn from the 1988 National Maternal and Infant Health Survey conducted by the National Center for Health Statistics. The objectives of the study were: (1) to examine the distribution of gestational ages of African American infants for selected variables reported for their families and (2) to describe risk factors associated with birth at 20–31 weeks of gestational age and at 32–36 weeks of gestational age. Risk factors examined include maternal age, maternal marital status, maternal living arrangements, maternal education, maternal work status, household income, gestational bleeding, month prenatal began, adequacy of prenatal care, parity, previous viable preterm birth, and behavioral factors of attitude toward pregnancy, smoking, drug, and alcohol use during pregnancy. Frequency distributions, cross tabulations, stratified analysis, and logistic regression analysis were used. ^ Risk factors associated with a 50 percent or more increase in preterm birth were cocaine use, low maternal education, teenaged mother, prenatal care deficits or overuse, and bleeding during the second half of pregnancy. The other risk factors of not living with the baby's father, smoking cigarettes and having a mistimed pregnancy carried statistically significance but lower strength of association. ^ Health care services, educational systems, and community organizations can develop and evaluate comprehensive health education and information campaigns that address preventable risk factors during pregnancy. Although preterm birth cannot always be prevented, preconception care can help identify and modify maternal risk and promote optimum health before conception. Quality care should include continued risk assessment, health promotion, and interventions. ^

Prevalence of depressive symptoms among Hispanic women attending a public health clinic

Background. Estimates of perinatal depression have ranged from 5% to more than 25% of women (Gavin et al. 2005). Although Hispanics have one of the highest birthrates, few studies have looked at the prevalence of depression among this population. This study aims to describe the prevalence of depressive symptoms among a sample of Hispanic women. Methods. A convenience sample of 439 Hispanic women were screened for depression using the Center for Epidemiologic Studies Depression Scale. Sociodemographic data relating to pregnancy were also collected. Results. Although bivariate analysis found several variables to be significant, multivariate analysis found only marital and pregnancy status to be significant in predicting depression. Conclusions. While marital and pregnancy status proved to the strongest predictors for depression, future research would benefit from collecting information on timing of pregnancy and postpartum to further explore the role of pregnancy status and depressive symptoms. ^

Contraceptive use in women by body mass index categories

The prevalence of obesity has increased sharply in the United States since the mid 1970's. Obese women who become pregnant are at increased risk of pregnancy complications for both mother and fetus. This study assessed whether women in higher body mass index (BMI) categories engage in the preventive behaviors of contraception more frequently than normal weight women. It also evaluated the type of contraception used by both obese and normal weight women. The study used cross-sectional data from 7 states participating in the Family Planning Module of the 2006 Behavioral Risk Factor Surveillance System (BRFSS). The Behavioral Risk Factor Surveillance System survey is an annual random digit dialed telephone survey of the non-institutionalized civilian population aged 18 years and older. The Family Planning Module was administered by Arizona, Kentucky, Minnesota, Missouri, Montana, Oregon, and Wisconsin. Of the 4,757 women who participated in the Family Planning Module, 2,244 (53.2%) were normal weight, 1,202 (25.6%) were overweight, and 1,072 (21.2%) were obese. The majority of these women 4,115 (86.2%) reported using some type of contraception to prevent pregnancy. Six hundred forty two women (13.8%) stated they did not use any type of contraception to prevent pregnancy. Within body mass index categories, 14% of normal weight women, 13% of overweight women, and 13.4% of obese women did not use any type of contraception. Neither the bivariate analysis nor the logistic regressions found body mass index categories to be statistically associated with contraceptive use. The relationship between body mass index categories and contraceptive method was found to be statistically significant. The predictive probability graph found that women at all levels of BMI have a lower probability of using barrier contraception methods as compared to procedural and hormonal methods. Hormonal contraception methods have the highest probability of use for women with a BMI of 15 to 25. In contrast, the probability of using procedural contraception methods is relatively flat and less than hormonal methods for BMI between 15 and 25. However, the probability of using procedural contraception increases dramatically with a BMI greater than 25. At a BMI greater than 42, women have a greater than 50% probability of using procedural contraception. Although a relationship between body mass index and contraception use was not found, contraception method was found to be associated with body mass index. The reasons why normal weight women prefer hormonal contraception while overweight/obese women are more likely to use procedural methods needs to be explored. By understanding the relationship between obesity and contraception, we can hopefully decrease unintended pregnancies and overall improve pregnancy related health outcomes. To determine if relationships between contraception use/type and body mass index exist, further research needs to be conducted on a national level. ^

The association between maternal use of spermicides, condoms, intra-uterine devices or progesterone and major structural birth defects

Birth defects occur in 1 of every 33 babies born in the United States, and are the leading cause of infant death. Mothers using contraceptives that become pregnant may continue to use their contraceptives after their first missed menstrual period, thus exposing their baby in utero to the contraceptive product. Progesterone is also sometimes prescribed during the first trimester of pregnancy to mothers with a history of miscarriages or infertility problems. To ensure the safety of these products, it is important to investigate whether there is an increased occurrence of babies born with birth defects to mothers using various contraceptive methods or progesterone in early pregnancy. Using data from the National Birth Defects Prevention Study (NBDPS), an ongoing multi-state, population based case-control study, this study assessed maternal exposures to IUDs, spermicides, condoms and progesterone in early pregnancy. ^ Progesterone used for threatened miscarriage during the first three months of pregnancy was associated with an increased occurrence of hypoplastic left heart (adjusted odds ratios (OR) 2.24, 95% CI 1.13-4.21), perimembranous ventricular septal defects (OR 1.64, 95% CI 1.10-2.41), septal associations (OR 2.52, 95% CI 1.45-4.24), esophageal atresia (OR 1.82, 95% CI 1.04-3.08), and hypospadias (OR 2.12, 95% CI 1.41-3.18). Mothers using progesterone for injectable contraception had increased (OR > 2.5), but insignificant odds ratios for anencephaly, septal associations, small intestinal atresias and omphalocel. Progesterone used for fertility was not associated with an increased occurrence of any birth defects examined. ^ Mothers using progesterone for fertility assistance and threatened miscarriage were very similar with respect to their demographics and pregnancy history. They also both reported similar types of progesterone. Thus, if progesterone was a causal risk factor for birth defects we would have expected to observe similar increases in risk among mothers using progesterone for both indications. Because we predominantly observed increased associations among mothers using progesterone for threatened miscarriage but not fertility assistance, it is possible the increased associations we observed were confounded by indication (i.e. progesterone was administered for vaginal bleeding which occurred as a sequelae to the formation of a congenital anomaly. ^ No significant increased associations were observed between maternal spermicide use during pregnancy and 26 of 27 types of structural malformations. While multiple statistical tests were performed we observed first trimester maternal spermicide use to be associated with a significant increased occurrence of perimembranous ventricular septal defects (OR 2.21, 95% CI 1.16-4.21). A decreased occurrence (OR < 1.0) was observed for several categories of birth defects among mothers who conceived in the first cycle after discontinuing the use of spermicides (22 of 28) or male condoms (23 of 33). ^ Overall the percent of IUD use was similar between mothers of controls and mothers of all cases in aggregate (crude OR 1.05, 95% CI 0.61-1.84). Power was limited to detect significant associations between IUD use and birth defects, however mothers using an IUD in the month immediately prior to conception or during pregnancy were not associated with an increase of birth defects. Limb defects and amniotic band sequence previously reported to be associated with IUD use during pregnancy were not found to occur among any mothers reporting the use of an IUD during pregnancy.^

Contraceptive attitudes and knowledge of female adolescents

Despite the recent decline in adolescent pregnancy rates, adolescent pregnancy continues to be a significant public health issue in the United States. The United States consistently reports the highest rate of adolescent pregnancy among developed countries. Adolescent mothers are more likely to have multiple pregnancies, to access welfare and other social services, and to be unmarried. Teen mothers are less likely to complete high school, enter college, and typically command much less earning power throughout their lifetime as compared to women who delay childbirth until later. Moreover, the United States spends approximately $9.1 billion annually on teen pregnancies. ^ Additionally disconcerting is recent data which demonstrates that the decline in teen pregnancy rates is leveling off and that the rate of adolescent pregnancy has increased for the first time since 1993. Contraceptive use is a key component to the prevention of adolescent pregnancy. Contraceptive nonuse and failure result in unintended pregnancies among adolescents. This review sought to assess the levels of knowledge and attitudes toward contraception among adolescent females.^ Levels of knowledge of contraception among adolescents are tolerable; however, there is substantial room for improvement. Misperceptions about the side effects and mechanisms of action of contraception are pervasive among this population. Adolescents who have low levels of knowledge regarding contraception tend to discontinue usage or use inconsistently. Attitudes toward contraception are greatly influenced by levels of knowledge. As a result, adolescents tend to develop more positive attitudes as misperceptions are abated. Moreover, clear disparities persist among adolescents with minority and young adolescents being at increased risk of pregnancy, poor contraceptive use, and insufficient knowledge about contraception.^ Understanding the level of knowledge of and attitudes toward contraceptives among adolescents is essential to the development of effective pregnancy prevention programs. In order to effectively reduce adolescent pregnancy, prevention initiatives must target the vulnerable populations and incorporate the necessary cultural components.^

US medical students' knowledge of obstetric fistula in developing countries

Obstetric fistula is a devastating child birth injury affecting millions of women worldwide. This paper explores the knowledge and understanding of medical students at the University of Texas Health Science Center at San Antonio regarding this global public health issue. Obstetric fistula has been eradicated in most industrialized nations, and has therefore faded from view of many modern medical organizations. The United Nations Population Fund has launched a “Campaign to End Fistula” in an attempt to bring global awareness to this preventable and treatable condition. Based on a survey administered to medical students at UTHSCSA, a baseline understanding of this disorder based on current curriculum is reviewed, with the objective of improving future physicians’ awareness of obstetric fistula. Despite a low survey response rate, there was a significant association between greater knowledge about causes, treatment, and complications of obstetric fistula and advanced years in medical school. However, the fourth year medical students averaged only a 70.5 percent of correct responses on the survey, indicating room for improvement in addressing this topic during medical school. ^

Epidemiological trends of influenza A positive patients hospitalized at St. Luke's Episcopal Hospital, Houston, Texas September, 2009--January, 2010

This study was a descriptive analysis of 437 influenza A positive inpatients and outpatients during the five month period between September, 2009 and January, 2010. The objective of the study was to describe the epidemiological trends of the total influenza A positive population and more specifically the clinical features of patients hospitalized with influenza A at St. Luke's Episcopal Hospital in Houston, Texas from September 2009 through January 2010. Eligible cases were included if they tested positive for influenza A test using the rapid antigen test and/or rRT-PCR. Hospitalized cases were included based on the laboratory confirmation of influenza A as well as hospital admission for at least 24 hours. Data was collected from medical record abstraction and included patient demographics, clinical history and history of chronic disease. Clinical findings in the differential diagnosis that led to laboratory-confirmation of influenza A as well as course of treatment during the hospital admission were summarized. Finally, co-morbid conditions charted during the hospital visit were reviewed and evaluated for associations with influenza A complications. During the study period, forty-eight patients were included in the study of which 27 tested positive for the H1N1 subtype. Females were more likely to be hospitalized than men. The median age of all patients admitted to St. Luke's Episcopal Hospital with influenza A was 42. The distribution for admitted cases was 15 White, 15 Black, and 18 Hispanic. Patients with co-morbid disease constituted 81% of the admissions for Influenza A. The presence of an underlying medical condition remains a risk factor for both seasonal and H1N1 influenza. Although respiratory conditions such as asthma and COPD are commonly associated with complications of seasonal influenza, patients with metabolic disorders such as kidney disease and/or diabetes were admitted more frequently (58%) during the study period. The patients in the study also of a much younger age than the age that is usually associated with complications of influenza infection, i.e. no patients greater than 65 years of age were admitted with a diagnosis of influenza A. Lower infection rates among elderly populations were similarly reported in other studies of influenza during the same time period. Older patient populations may benefit from antibodies to previous H1N1 strains that have circulated during the twentieth century, whereas younger age groups lack these exposures.^