Computational tools to investigate genetic cardiac channelopathies

The aim of this perspective article is to share with the community of ion channel scientists our thoughts and expectations regarding the increasing role that computational tools will play in the future of our field. The opinions and comments detailed here are the result of a 3-day long international exploratory workshop that took place in October 2013 and that was supported by the Swiss National Science Foundation.

Glucagon-like peptide-1 receptor imaging for the localisation of insulinomas: a prospective multicentre imaging study

BACKGROUND Small benign insulinomas are hard to localise, leading to difficulties in planning of surgical interventions. We aimed to prospectively assess the insulinoma detection rate of single-photon emission CT in combination with CT (SPECT/CT) with a glucagon-like peptide-1 receptor avid radiotracer, and compare detection rates with conventional CT/MRI techniques. METHODS In our prospective imaging study, we enrolled adults aged 25-81 years at centres in Germany, Switzerland, and the UK. Eligible patients had proven clinical and biochemical endogenous hyperinsulinaemic hypoglycaemia and no evidence for metastatic disease on conventional imaging. CT/MRI imaging was done at referring centres according to standard protocols. At three tertiary nuclear medicine centres, we used whole body planar images and SPECT/CT of the abdomen up to 168 h after injection of (111)In-[Lys40(Ahx-DTPA-(111)In)NH2]-exendin-4 ((111)In-DTPA-exendin-4) to identify insulinomas. Consenting patients underwent surgery and imaging findings were confirmed histologically. FINDINGS Between Oct 1, 2008, and Dec 31, 2011, we recruited 30 patients. All patients underwent (111)In-DTPA-exendin-4 imaging, 25 patients underwent surgery (with histological analysis), and 27 patients were assessed with CT/MRI. (111)In-DTPA-exendin-4 SPECT/CT correctly detected 19 insulinomas and four additional positive lesions (two islet-cell hyperplasia and two uncharacterised lesions) resulting in a positive predictive value of 83% (95% CI 62-94). One true negative (islet-cell hyperplasia) and one false negative (malignant insulinoma) result was identified in separate patients by (111)In-DTPA-exendin-4 SPECT/CT. Seven patients (23%) were referred to surgery on the basis of (111)In-DTPA-exendin-4 imaging alone. For 23 assessable patients, (111)In-DTPA-exendin-4 SPECT/CT had a higher sensitivity (95% [95% CI 74-100]) than did CT/MRI (47% [27-68]; p=0·011). INTERPRETATION (111)In-DTPA-exendin-4 SPECT/CT could provide a good second-line imaging strategy for patients with negative results on initial imaging with CT/MRI. FUNDING Oncosuisse, the Swiss National Science Foundation, and UK Department of Health.

Inequality in Income and Wealth in Switzerland from 1970 to 2010

The supposed rise of inequality in income and wealth is a much-discussed issue. Since in a number of industrialized countries a trend towards more inequality was observed over the last decades, it is often assumed that Switzerland has experienced a similar development. Yet, although a variety of studies exists that provide inequality estimates for the Swiss society at different points in time, no conclusive picture of the changes in inequality can be drawn from these studies. For example, recent estimates by the Swiss Federal Statistical Office indicate that – against expectations – inequality in disposable equivalent-incomes has not risen since the end of the 1990ies, whereas other studies indicate that earnings from employment – especially top salaries – have become more unequal. The reasons for the inconclusive picture are manifold. For example, trends might have been different for different income types and results might strongly depend on the quality of the used data. To close the knowledge gap in inequality research in Switzerland a new Swiss National Science Foundation project by the University of Bern and the Bern University of Applied Sciences has been started in 2013. Individual tax data from cantons will be analyzed along with aggregate data from the Swiss Federal Tax Administration, covering a period from the early 1970ies to the present. The goal is to gain a systematic overview of the development of inequality in income and wealth in Switzerland as a whole and within cantons, and to determine how changes can be explained. In our talk we will present first results from this project.

New Law against an Old State: Land Restitution as a Transition to Justice in Post-Apartheid South Africa?

The research on which this text is based has been financially supported by the Berne University Research Foundation (2009–2011) as well as by an Ambizione Research Fellowship of the Swiss National Science Foundation (2012–2014). During my stays in South Africa, the Departments of Anthropology at the University of the Witwatersrand, Johannesburg, and the University of South Africa (UNISA), Pretoria, provided me with welcoming and inspiring research environments. This article benefitted greatly from engaged discussions around its presentation at various occasions, notably our ECAS 2011 panel Transition and Justice: Negotiating the Terms of New Beginnings in Africa, held in Uppsala. I am particularly grateful to my co-convener and co-editor Gerhard Anders as well as Laurens Bakker, Keebet von Benda-Beckmann, Ben Cousins, Julia Eckert, Marion Fresia, Vinodh Jaichand, Steffen Jensen, Tim Kelsall, Hanri Mostert, Johanna Mugler, David O'Kane, Julia Pauli, Mats Utas, Julia Zenker and the anonymous referees of Development and Change for their critical engagements.

Psychological adaptation to spousal loss in old age: The role of personality

Spousal loss is an inevitable critical life event for most individuals in old age, mostly associated with a negative impact on various well-being measures, ie. lower life satisfaction, higher rates of loneliness and depressive symptoms compared to married peers. While the negative effects on well-being are well documented in literature, the modifying factors accounting for the large variability in adaptation to loss are discussed controversially. The potential relevance of personality in the adaptation process has rarely been examined and findings regarding the role of time since loss are contradictory. Based on a vulnerability-stress-model this contribution aims a) to compare psychological well-being of bereaved individuals with married counterparts and b) to investigate the protective effects of different personality traits (Big Five, resilience), and the role of time since loss for adaptation in terms of life satisfaction, loneliness and depression. Data from a questionnaire study about the loss of a spouse in middle and old age in the German- and French-speaking parts of Switzerland are reported. The study is part of the Swiss National Centre of Competence in Research LIVES (Swiss National Science Foundation). The sample consists of 351 widowed persons (39% men, widowed since 0 - 5 years), and 605 married controls (50% men), aged 60 - 89 years. Group comparisons reveal the detrimental effect of spousal bereavement on all indicators of psychological adaptation. Results from hierarchical regression analyses show furthermore, that the effect of spousal loss on all psychological outcomes is moderated by personality traits. Separate analyses with the group of bereaved individuals suggest, that the protective effect of personality varies by the time passed since loss. Our results contribute to a better understanding of the variability in psychological adaptation to spousal loss in old age and give hints for counselling practice.

Subclinical thyroid dysfunction and the risk for fractures: a systematic review and meta-analysis.

BACKGROUND Data on the association between subclinical thyroid dysfunction and fractures conflict. PURPOSE To assess the risk for hip and nonspine fractures associated with subclinical thyroid dysfunction among prospective cohorts. DATA SOURCES Search of MEDLINE and EMBASE (1946 to 16 March 2014) and reference lists of retrieved articles without language restriction. STUDY SELECTION Two physicians screened and identified prospective cohorts that measured thyroid function and followed participants to assess fracture outcomes. DATA EXTRACTION One reviewer extracted data using a standardized protocol, and another verified data. Both reviewers independently assessed methodological quality of the studies. DATA SYNTHESIS The 7 population-based cohorts of heterogeneous quality included 50,245 participants with 1966 hip and 3281 nonspine fractures. In random-effects models that included the 5 higher-quality studies, the pooled adjusted hazard ratios (HRs) of participants with subclinical hyperthyroidism versus euthyrodism were 1.38 (95% CI, 0.92 to 2.07) for hip fractures and 1.20 (CI, 0.83 to 1.72) for nonspine fractures without statistical heterogeneity (P = 0.82 and 0.52, respectively; I2= 0%). Pooled estimates for the 7 cohorts were 1.26 (CI, 0.96 to 1.65) for hip fractures and 1.16 (CI, 0.95 to 1.42) for nonspine fractures. When thyroxine recipients were excluded, the HRs for participants with subclinical hyperthyroidism were 2.16 (CI, 0.87 to 5.37) for hip fractures and 1.43 (CI, 0.73 to 2.78) for nonspine fractures. For participants with subclinical hypothyroidism, HRs from higher-quality studies were 1.12 (CI, 0.83 to 1.51) for hip fractures and 1.04 (CI, 0.76 to 1.42) for nonspine fractures (P for heterogeneity = 0.69 and 0.88, respectively; I2 = 0%). LIMITATIONS Selective reporting cannot be excluded. Adjustment for potential common confounders varied and was not adequately done across all studies. CONCLUSION Subclinical hyperthyroidism might be associated with an increased risk for hip and nonspine fractures, but additional large, high-quality studies are needed. PRIMARY FUNDING SOURCE Swiss National Science Foundation.

Self-burning – A rare suicide method in switzerland and other industrialised nations – A review

News items reporting self-immolation by Tibetans have been on the increase in recent years. After examining the corpse of a Swiss man who had committed suicide by deliberate self-burning, we wondered how often this occurs in Switzerland. The Federal Statistics Office (FSO) does not register self-burning specifically so no official national data on this form of suicide are available. However, we had access to the data from a Swiss National Science Foundation (SNSF) project Suicides in Switzerland between 2000 and 2010, which collected information on all (4885) cases of suicide investigated by the various institutes of forensic medicine. From this data pool we extracted 50 cases (1.02%) of suicide by selfburning, in order to determine the details and to identify the possible reasons for choosing this method. To look at our results in the light of studies from other countries, we searched the literature for studies that had also retrospectively examined suicide by self-immolation based on forensic records. Our results showed that, on the whole, personal aspects of selfburning in Switzerland do not differ from those in other industrialised nations. Some data, including religious and sociocultural background, were unfortunately missing – not only from our study but also from the similar ones. In our opinion, the most important prevention strategy is to make healthcare professionals more aware of this rare method of suicide.

Dyadic action control in overweight and obese couples: Effectiveness of a randomized controlled trial to promote physical activity.

BACKGROUND: Enhancing physical activity in overweight and obese individuals is an important means to promote health in this target population. The Health Action Process Approach (HAPA), which was the theoretical framework of this study, focuses on individual self-regulation variables for successful health behavior change. One key self-regulation variable of this model is action control with its three subfacets awareness of intentions, self-monitoring and regulatory effort. The social context of individuals, however, is usually neglected in common health behavior change theories. In order to integrate social influences into the HAPA, this randomized controlled trial investigated the effectiveness of a dyadic conceptualization of action control for promoting physical activity. METHODS/DESIGN: This protocol describes the design of a single-blind randomized controlled trial, which comprises four experimental groups: a dyadic action control group, an individual action control group and two control groups. Participants of this study are overweight or obese, heterosexual adult couples who intend to increase their physical activity. Blocking as means of a gender-balanced randomization is used to allocate couples to conditions and partners to either being the target person of the intervention or to the partner condition. The ecological momentary intervention takes place in the first 14 days after baseline assessment and is followed by another 14 days diary phase without intervention. Follow-ups are one month and six months later. Subsequent to the six-months follow-up another 14 days diary phase takes place.The main outcome measures are self-reported and accelerometer-assessed physical activity. Secondary outcome measures are Body Mass Index (BMI), aerobic fitness and habitual physical activity. DISCUSSION: This is the first study examining a dyadic action control intervention in comparison to an individual action control condition and two control groups applying a single-blind randomized control trial. Challenges with running couples studies as well as advantages and disadvantages of certain design-related decisions are discussed. This RCT was funded by the Swiss National Science Foundation (PP00P1_133632/1) and was registered on 27/04/2012 at http://www.isrctn.com/ISRCTN15705531.

A Dyadic Action Control Trial in Overweight and Obese Couples (DYACTIC)

BACKGROUND: Enhancing physical activity in overweight and obese individuals is an important means to promote health in this target population. The Health Action Process Approach (HAPA), which was the theoretical framework of this study, focuses on individual self-regulation variables for successful health behavior change. One key self-regulation variable of this model is action control with its three subfacets awareness of intentions, self-monitoring and regulatory effort. The social context of individuals, however, is usually neglected in common health behavior change theories. In order to integrate social influences into the HAPA, this randomized controlled trial investigated the effectiveness of a dyadic conceptualization of action control for promoting physical activity. METHODS/DESIGN: This protocol describes the design of a single-blind randomized controlled trial, which comprises four experimental groups: a dyadic action control group, an individual action control group and two control groups. Participants of this study are overweight or obese, heterosexual adult couples who intend to increase their physical activity. Blocking as means of a gender-balanced randomization is used to allocate couples to conditions and partners to either being the target person of the intervention or to the partner condition. The ecological momentary intervention takes place in the first 14 days after baseline assessment and is followed by another 14 days diary phase without intervention. Follow-ups are one month and six months later. Subsequent to the six-months follow-up another 14 days diary phase takes place.The main outcome measures are self-reported and accelerometer-assessed physical activity. Secondary outcome measures are Body Mass Index (BMI), aerobic fitness and habitual physical activity. DISCUSSION: This is the first study examining a dyadic action control intervention in comparison to an individual action control condition and two control groups applying a single-blind randomized control trial. Challenges with running couples studies as well as advantages and disadvantages of certain design-related decisions are discussed. This RCT was funded by the Swiss National Science Foundation (PP00P1_133632/1) and was registered on 27/04/2012 at http://www.isrctn.com/ISRCTN15705531.

Bovine coccygeal intervertebral discs contain multipotent Tie2+ cells which can differentiate into osteogenic and adipogenic lineages

Question: The intervertebral disc (IVD) has a limited regenerative potential and low back pain represents a leading cause of disability [1]. IVD repair strategies require an appropriate cell source that is able to regenerate the damaged tissue such as progenitor stem cells. Recently, progenitor cells that are positive for the angiopoietin re- ceptor (Tie2) in the nucleus pulposus were identified [2]. Here we isolated primary cells from bovine IVD and sorted bovine nucleus pulposus progenitor cells (NPPC) for the marker Tie2. Furthermorewe tested whether Tie2 expressing cells can differentiate into os- teogenic and adipogenic lineages in vitro. Methods: NP cells were obtained from 1 year old bovine tails by sequential digestion with pronase for 1 h and collagenase over- night. Sorted Tie2- and Tie2+ cells were cultured in osteogenic and adipogenic medium for 3 weeks. The formed cell layers from both subpopulations were stained for calcium deposition and fat droplets. Colony forming units were prepared for both cell sus- pensions in methylcellulose-based medium and formed colonies ([10 cells) were analyzed macroscopically after 8 days. Results: After 3 weeks of culture, sorted Tie2+ cells were able to differentiate into osteocytes and adipocytes as characterized by cal- cium deposition and fat droplet formation. By contrast, Tie2- cells generated a weak staining for calcium and no fat droplets were ob- tained (Fig. 1). Sorted Tie2- and Tie2+ subpopulations of cells both formed colonies, however with different morphologies. The colonies formed from Tie2+ cells were spheroid in shape whereas those from Tie2- cells were spread and fibroblastic. Conclusion: Our data showed that Tie2+ cells of the nucleus pul- posus cells are progenitor-like cells that are able to differentiate into osteogenic and adipogenic lineages. Sorting of NPPC for Tie2 may represent a promising strategy with the potential to be used in the clinics for treatment of intervertebral disc damage. References 1. Freemont AJ (2009) The cellular pathobiology of the degenerate intervertebral disc and discogenic back pain. Rheumatology (Oxford) 48:5–10 2. Sakai D, Nakamura Y, Nakai T et al (2012) Exhaustion of nucleus pulposus progenitor cells with ageing and degeneration of the intervertebral disc. Nat Commun 3:1264 Acknowledgments: This project was funded by two projects of the Swiss National Science Foundation grant number #IZK0Z3_154384 and #310030_153411.

Trajectories of psychological adaptation to marital breakup after a long-term marriage

While the negative effects of divorce on well-being are well documented in research literature, the large individual differences in psychological adaptation over time are still not well understood. This is especially the case for marital breakup after long-term marriage, which is still a neglected research topic. Against this background, the aim of the present contribution is to shed light on the various trajectories of psychological adaptation to marital breakup after a long-term relationship. Data stem from a longitudinal survey study, which is part of the Swiss National Centre of Competence in Research ‘LIVES – Overcoming vulnerability: life course perspectives’ (funded by the Swiss National Science Foundation). Our analyses are based on results of an exploratory latent profile analysis performed at the first assessment in 2012 among 308 divorced participants aged 45 – 65 years, who divorced after an average of 25 years of marriage (Perrig-Chiello, Hutchison, & Morselli, 2014). Five different groups regarding psychological adaptation to marital breakup (i.e. life satisfaction, depression, hopelessness, subjective health, and mourning) were identified. They were composed of two larger groups of individuals that adapted quite well or very well (“average copers”, n=151 and “resilients”, n=90) and of three smaller groups with major difficulties to adjust to the new situation (“vulnerables”, n= 18; “malcontens”, n= 37 and “resigned ones”, n=12). Clusters differed statistically significant regarding personality variables, time since separation, current relationship status, and financial situation. In the present contribution, we want to investigate the course of adaptation of the five classes two years later by using latent transition analysis. Furthermore, we aim to examine which variables in terms of personality, relationship status, variables of the context of the separation and socio-demographic variables are crucial for change or stability in levels of adaptation in the different classes. The evaluation of the trajectories of adaptation to this critical life event and the identification of variables that enhance the adaptation over time is essential for developing more differentiated measures in counselling as well as intervention techniques in clinical and social services.

Evaluation of HA-fibrin-based hydrogel for restoration of degenerated intervertebral disc

Introduction: Intervertebral disc degeneration is associated with loss of nucleus pulposus (NP) tissue and reduced disc height[1]. A number of therapies, including synthetic and natural biomaterials, have been developed to restore full disc function and to minimize the pain and disability caused by this disease. Fibrin-based biomaterials are used as a replacement for NP or as a cell carrier for tissue engineering approaches[2]. While the behavior of such gels is well-characterized from a material point of view, little is known about their contribution to intervertebral disc (IVD) restoration under dynamic loads. The aim of the present study is the evaluation of a hyaluronic acid fibrin-based hydrogel (ProCore) used to repair an in vitro model of disc degeneration under dynamic loading. Methods: In vitro model of disc degeneration was induced in intact coccygeal bovine IVD by papain digestion of the NP as previously described[3]. In order to characterize fibrin hydrogels, four experimental groups were considered: 1) intact IVD (control), 2) IVD injected with PBS, 3) injection of hydrogels in degenerative IVD and 4) injection of hydrogels in combination with human bone marrow-derived mesenchymal stem cells (MSC) in degenerative IVD. All of the groups were subjected to dynamic loading protocols consisting of 0.2MPa static compression superimposed with ±2° torsion at 0.2Hz for 8h per day and maintained for 7 days. Additionally, one group consisted of degenerative IVD injected with hydrogel and subjected to static compression. Disc heights were monitored after the duration of the loading and compared to the initial disc height. The macrostructure of the formed tissue and the cellular distribution was evaluated by histological means. Results: After one week of loading, the degenerative IVD filled with hydrogel in combination with MSC (dynamic load), hydrogels (dynamic load) and hydrogels (static load) showed a reduction in height by 30%, 15% and 20%, respectively, as compared to their initial disc height. Histological sections showed that the HA-fibrin gel fully occupied the nucleotomized region of the disc and that fibrin was effective in filling the discontinuities of the cavity region. Furthermore, the cells were homogenously distributed along the fibrin hydrogels after 7 days of loading. Discussion: In this study, we showed that fibrin hydrogels showed a good integration within the papain-induced model of disc degeneration and can withstand the applied loads. Fibrin hydrogels can contribute to disc restoration by possibly maintaining adequate stiffness of the tissue and thus preventing disorganization of the surrounding IVD. References: 1. Jarman, J.P., Arpinar, V.E., Baruah, D., Klein, A.P., Maiman, D.J., and Tugan Muftuler, L. (2014). Intervertebral disc height loss demonstrates the threshold of major pathological changes during degeneration. Eur Spine J . 2. Colombini, A., Ceriani, C., Banfi, G., Brayda-Bruno, M., and Moretti, M. (2014). Fibrin in intervertebral disc tissue engineering. Tissue Eng Part B Rev . 3. Chan, S.C., Bürki, A., Bonél, H.M., Benneker, L.M., and Gantenbein-Ritter, B. (2013). Papain-induced in vitro disc degeneration model for the study of injectable nucleus pulposus therapy. Spine J 13, 273-283. Acknowledgement We thank the Swiss National Science Foundation SNF #310030_153411 for funding.

Adjunct prednisone therapy for patients with community-acquired pneumonia: a multicentre, double-blind, randomised, placebo-controlled trial

BACKGROUND Clinical trials yielded conflicting data about the benefit of adding systemic corticosteroids for treatment of community-acquired pneumonia. We assessed whether short-term corticosteroid treatment reduces time to clinical stability in patients admitted to hospital for community-acquired pneumonia. METHODS In this double-blind, multicentre, randomised, placebo-controlled trial, we recruited patients aged 18 years or older with community-acquired pneumonia from seven tertiary care hospitals in Switzerland within 24 h of presentation. Patients were randomly assigned (1:1 ratio) to receive either prednisone 50 mg daily for 7 days or placebo. The computer-generated randomisation was done with variable block sizes of four to six and stratified by study centre. The primary endpoint was time to clinical stability defined as time (days) until stable vital signs for at least 24 h, and analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00973154. FINDINGS From Dec 1, 2009, to May 21, 2014, of 2911 patients assessed for eligibility, 785 patients were randomly assigned to either the prednisone group (n=392) or the placebo group (n=393). Median time to clinical stability was shorter in the prednisone group (3·0 days, IQR 2·5-3·4) than in the placebo group (4·4 days, 4·0-5·0; hazard ratio [HR] 1·33, 95% CI 1·15-1·50, p<0·0001). Pneumonia-associated complications until day 30 did not differ between groups (11 [3%] in the prednisone group and 22 [6%] in the placebo group; odds ratio [OR] 0·49 [95% CI 0·23-1·02]; p=0·056). The prednisone group had a higher incidence of in-hospital hyperglycaemia needing insulin treatment (76 [19%] vs 43 [11%]; OR 1·96, 95% CI 1·31-2·93, p=0·0010). Other adverse events compatible with corticosteroid use were rare and similar in both groups. INTERPRETATION Prednisone treatment for 7 days in patients with community-acquired pneumonia admitted to hospital shortens time to clinical stability without an increase in complications. This finding is relevant from a patient perspective and an important determinant of hospital costs and efficiency. FUNDING Swiss National Science Foundation, Viollier AG, Nora van Meeuwen Haefliger Stiftung, Julia und Gottfried Bangerter-Rhyner Stiftung.

Diagnostic Accuracy of Copeptin in the Differential Diagnosis of the Polyuria-polydipsia Syndrome: A Prospective Multicenter Study

CONTEXT The polyuria-polydipsia syndrome comprises primary polydipsia (PP) and central and nephrogenic diabetes insipidus (DI). Correctly discriminating these entities is mandatory, given that inadequate treatment causes serious complications. The diagnostic "gold standard" is the water deprivation test with assessment of arginine vasopressin (AVP) activity. However, test interpretation and AVP measurement are challenging. OBJECTIVE The objective was to evaluate the accuracy of copeptin, a stable peptide stoichiometrically cosecreted with AVP, in the differential diagnosis of polyuria-polydipsia syndrome. DESIGN, SETTING, AND PATIENTS This was a prospective multicenter observational cohort study from four Swiss or German tertiary referral centers of adults >18 years old with the history of polyuria and polydipsia. MEASUREMENTS A standardized combined water deprivation/3% saline infusion test was performed and terminated when serum sodium exceeded 147 mmol/L. Circulating copeptin and AVP levels were measured regularly throughout the test. Final diagnosis was based on the water deprivation/saline infusion test results, clinical information, and the treatment response. RESULTS Fifty-five patients were enrolled (11 with complete central DI, 16 with partial central DI, 18 with PP, and 10 with nephrogenic DI). Without prior thirsting, a single baseline copeptin level >21.4 pmol/L differentiated nephrogenic DI from other etiologies with a 100% sensitivity and specificity, rendering a water deprivation testing unnecessary in such cases. A stimulated copeptin >4.9 pmol/L (at sodium levels >147 mmol/L) differentiated between patients with PP and patients with partial central DI with a 94.0% specificity and a 94.4% sensitivity. A stimulated AVP >1.8 pg/mL differentiated between the same categories with a 93.0% specificity and a 83.0% sensitivity. LIMITATION This study was limited by incorporation bias from including AVP levels as a diagnostic criterion. CONCLUSION Copeptin is a promising new tool in the differential diagnosis of the polyuria-polydipsia syndrome, and a valid surrogate marker for AVP. Primary Funding Sources: Swiss National Science Foundation, University of Basel.

The need for second-line antiretroviral therapy in adults in sub-Saharan Africa up to 2030: a mathematical modelling study.

BACKGROUND The number of patients in need of second-line antiretroviral drugs is increasing in sub-Saharan Africa. We aimed to project the need of second-line antiretroviral therapy in adults in sub-Saharan Africa up to 2030. METHODS We developed a simulation model for HIV and applied it to each sub-Saharan African country. We used the WHO country intelligence database to estimate the number of adult patients receiving antiretroviral therapy from 2005 to 2014. We fitted the number of adult patients receiving antiretroviral therapy to observed estimates, and predicted first-line and second-line needs between 2015 and 2030. We present results for sub-Saharan Africa, and eight selected countries. We present 18 scenarios, combining the availability of viral load monitoring, speed of antiretroviral scale-up, and rates of retention and switching to second-line. HIV transmission was not included. FINDINGS Depending on the scenario, 8·7-25·6 million people are expected to receive antiretroviral therapy in 2020, of whom 0·5-3·0 million will be receiving second-line antiretroviral therapy. The proportion of patients on treatment receiving second-line therapy was highest (15·6%) in the scenario with perfect retention and immediate switching, no further scale-up, and universal routine viral load monitoring. In 2030, the estimated range of patients receiving antiretroviral therapy will remain constant, but the number of patients receiving second-line antiretroviral therapy will increase to 0·8-4·6 million (6·6-19·6%). The need for second-line antiretroviral therapy was two to three times higher if routine viral load monitoring was implemented throughout the region, compared with a scenario of no further viral load monitoring scale-up. For each monitoring strategy, the future proportion of patients receiving second-line antiretroviral therapy differed only minimally between countries. INTERPRETATION Donors and countries in sub-Saharan Africa should prepare for a substantial increase in the need for second-line drugs during the next few years as access to viral load monitoring improves. An urgent need exists to decrease the costs of second-line drugs. FUNDING World Health Organization, Swiss National Science Foundation, National Institutes of Health.