Photophysical image analysis: Unsupervised probabilistic thresholding for images from electron-multiplying charge-coupled devices.

We introduce the concept photophysical image analysis (PIA) and an associated pipeline for unsupervised probabilistic image thresholding for images recorded by electron-multiplying charge-coupled device (EMCCD) cameras. We base our approach on a closed-form analytic expression for the characteristic function (Fourier-transform of the probability mass function) for the image counts recorded in an EMCCD camera, which takes into account both stochasticity in the arrival of photons at the imaging camera and subsequent noise induced by the detection system of the camera. The only assumption in our method is that the background photon arrival to the imaging system is described by a stationary Poisson process (we make no assumption about the photon statistics for the signal). We estimate the background photon statistics parameter, λbg, from an image which contains both background and signal pixels by use of a novel truncated fit procedure with an automatically determined image count threshold. Prior to this, the camera noise model parameters are estimated using a calibration step. Utilizing the estimates for the camera parameters and λbg, we then introduce a probabilistic thresholding method, where, for the first time, the fraction of misclassified pixels can be determined a priori for a general image in an unsupervised way. We use synthetic images to validate our a priori estimates and to benchmark against the Otsu method, which is a popular unsupervised non-probabilistic image thresholding method (no a priori estimates for the error rates are provided). For completeness, we lastly present a simple heuristic general-purpose segmentation method based on the thresholding results, which we apply to segmentation of synthetic images and experimental images of fluorescent beads and lung cell nuclei. Our publicly available software opens up for fully automated, unsupervised, probabilistic photophysical image analysis.

Metabolic Syndrome Traits Increase the Risk of Major Adverse Liver Outcomes in Type 2 Diabetes.

OBJECTIVE: Type 2 diabetes (T2D) increases the risk for major adverse liver outcomes (MALOs), including cirrhosis and its complications. Patients with T2D frequently have other traits of the metabolic syndrome (MetS). It remains uncertain whether there is a synergistic effect of accumulating MetS traits on future MALO risk. RESEARCH DESIGN AND METHODS: Patients with T2D without a history of liver disease were identified from national registers in Sweden from 1998 to 2021. MetS traits included hypertension, low HDL level, hypertriglyceridemia, obesity, and albuminuria, in addition to T2D. MALO events were identified based on administrative coding from national registers until 31 October 2022. Data were analyzed using Cox regression models. RESULTS: In total, 230,992 patients were identified (median age 64 years; 58% male), of whom 3,215 (1.39%) developed MALOs over a median follow-up of 9.9 years. Compared with patients with one MetS trait (only T2D) at baseline, those with more than one MetS trait had a higher rate of MALOs (adjusted hazard ratio [aHR] 2.33, 95% CI 1.53-3.54). The rate of MALOs increased progressively with increasing numbers of MetS traits at baseline (aHR 1.28 per added trait, 95% CI 1.23-1.33). During follow-up, patients who acquired additional MetS traits had a progressively higher rate of MALOs. The MetS trait with the largest association with incident MALOs was hypertension (aHR 2.06, 95% CI 1.57-2.71). CONCLUSIONS: Having or acquiring additional traits of MetS increase the rate of progression to MALOs in patients with T2D. These results could be used to inform screening initiatives for liver disease.

Geometry-Dependent Elastic Flow Dynamics in Micropillar Arrays.

Regular device-scale DNA waves for high DNA concentrations and flow velocities have been shown to emerge in quadratic micropillar arrays with potentially strong relevance for a wide range of microfluidic applications. Hexagonal arrays constitute another geometry that is especially relevant for the microfluidic pulsed-field separation of DNA. Here, we report on the differences at the micro and macroscopic scales between the resulting wave patterns for these two regular array geometries and one disordered array geometry. In contrast to the large-scale regular waves visible in the quadratic array, in the hexagonal arrays, waves occur in a device-scale disordered zig-zag pattern with fluctuations on a much smaller scale. We connect the large-scale pattern to the microscopic flow and observe flow synchronization that switches between two directions for both the quadratic and hexagonal arrays. We show the importance of order using the disordered array, where steady-state stationary and highly fluctuating flow states persist in seemingly random locations across the array. We compare the flow dynamics of the arrays to that in a device with sparsely distributed pillars. Here, we observe similar vortex shedding, which is clearly observable in the quadratic and disordered arrays. However, the shedding of these vortices couples only in the flow direction and not laterally as in the dense, ordered arrays. We believe that our findings will contribute to the understanding of elastic flow dynamics in pillar arrays, helping us elucidate the fundamental principles of non-Newtonian fluid flow in complex environments as well as supporting applications in engineering involving e.g., transport, sorting, and mixing of complex fluids.

Using symmetry to control viscoelastic waves in pillar arrays.

Solutions of macromolecules exhibit viscoelastic properties and unlike Newtonian fluids, they may break time-reversal symmetry at low Reynolds numbers resulting in elastic turbulence. Furthermore, under some conditions, instead of the chaotic turbulence, the result is large-scale waves in the form of cyclic spatial and temporal concentration variations, as has been shown for macromolecular DNA flowing in microfluidic pillar arrays. We here demonstrate how altering the symmetry of the individual pillars can be used to influence the symmetry of these waves. We control the extent of instabilities in viscoelastic flow by leveraging the effects of the symmetry of the pillars on the waves, demonstrating suppressed viscoelastic fluctuations with relevance for transport and sorting applications, or conversely opening up for enhanced viscoelasticity-mediated mixing. The onset of waves, which changes flow resistance, occurs at different Deborah numbers for flow in different directions through the array of triangular pillars, thus breaking the symmetry of the flow resistance along the device, opening up for using the occurrence of the waves to construct a fluidic diode.

Paricalcitol and Extended-Release Calcifediol for Treatment of Secondary Hyperparathyroidism in Non-Dialysis Chronic Kidney Disease: Results From a Network Meta-Analysis.

CONTEXT: Secondary hyperparathyroidism (SHPT) is a complication of chronic kidney disease (CKD) affecting mineral and bone metabolism and characterized by excessive parathyroid hormone (PTH) production and parathyroid hyperplasia. OBJECTIVE: The objective of this analysis was to compare the efficacy and adverse effects of extended-release calcifediol (ERC) and paricalcitol (PCT) by assessing their effect on the biomarkers PTH, calcium, and phosphate in patients with non-dialysis CKD (ND-CKD). METHODS: A systematic literature research was performed in PubMed to identify randomized control trials (RCTs). Quality assessment was done with the GRADE method. The effects of ERC vs PCT were compared using random effects in a frequentist setting. RESULTS: Nine RCTs comprising 1426 patients were included in the analyses. The analyses were performed on 2 overlapping networks, due to nonreporting of outcomes in some of the included studies. No head-to-head trials were identified. No statistically significant differences in PTH reduction were found between PCT and ERC. Treatment with PCT showed statistically significant increases in calcium compared with ERC (0.2 mg/dL increase; 95% CI, -0.37 to -0.05 mg/dL). No differences in effects on phosphate were observed. CONCLUSION: This network meta-analysis showed that ERC is comparable in lowering PTH levels vs PCT. ERC displayed avoidance of potentially clinically relevant increases in serum calcium, offering an effective and well-tolerated treatment option for the management of SHPT in patients with ND-CKD.

Short and long-range cyclic patterns in flows of DNA solutions in microfluidic obstacle arrays.

We observe regular patterns emerging across multiple length scales with high-concentration DNA solutions in microfluidic pillar arrays at low Reynolds numbers and high Deborah numbers. Interacting vortices between pillars lead to long-range order in the form of large travelling waves consisting of DNA at high concentration and extension. Waves are formed in quadratic arrays of pillars, while randomizing the position of the pillar in each unit cell of a quadratic array leads to suppression of the long-range patterns. We find that concentrations exceeding the overlap concentration of the DNA enables the waves, and exploring the behavior of the waves as a function of flow rate, buffer composition, concentration and molecular length, we identify elastic effects as central to the origin of the waves. Our work may not only help increase the low throughput that often limits sample processing in microfluidics, it may also provide a platform for further studies of the underlying viscoelastic mechanisms.

High-Throughput Separation of Long DNA in Deterministic Lateral Displacement Arrays.

Length-based separation of DNA remains as relevant today as when gel electrophoresis was introduced almost 100 years ago. While new, long-read genomics technologies have revolutionised accessibility to powerful genomic data, the preparation of samples has not proceeded at the same pace, with sample preparation often constituting a considerable bottleneck, both in time and difficulty. Microfluidics holds great potential for automated, sample-to-answer analysis via the integration of preparatory and analytical steps, but for this to be fully realised, more versatile, powerful and integrable unit operations, such as separation, are essential. We demonstrate the displacement and separation of DNA with a throughput that is one to five orders of magnitude greater than other microfluidic techniques. Using a device with a small footprint (23 mm × 0.5 mm), and with feature sizes in the micrometre range, it is considerably easier to fabricate than parallelized nano-array-based approaches. We show the separation of 48.5 kbp and 166 kbp DNA strands achieving a significantly improved throughput of 760 ng/h, compared to previous work and the separation of low concentrations of 48.5 kbp DNA molecules from a massive background of sub 10 kbp fragments. We show that the extension of DNA molecules at high flow velocities, generally believed to make the length-based separation of long DNA difficult, does not place the ultimate limitation on our method. Instead, we explore the effects of polymer rotations and intermolecular interactions at extremely high DNA concentrations and postulate that these may have both negative and positive influences on the separation depending on the detailed experimental conditions.

Risk of major osteoporotic fracture after first, second and third fracture in Swedish women aged 50 years and older.

BACKGROUND: Osteoporosis affects approximately one in five European women and leads to fragility fractures, which result in poor health, social and economic consequences. Fragility fractures are a strong risk factor for subsequent major osteoporotic fracture (MOF), with risk of MOF being elevated in the 1-2 years following an earlier fracture, a concept described as "imminent risk". This study examines risk of subsequent MOF in patients with one, two or three prior fractures by age and type of fracture. METHODS: In this retrospective, observational cohort study, Swedish women aged ≥50 years with ≥1 any clinical fragility fracture between July 1, 2006 and December 31, 2012 were identified from Sweden's National Patient Register. Each patient was age- and sex-matched to three controls without history of fracture. Group 1 women included those with one fragility fracture during the study period; Group 2 included those with two fragility fractures; and Group 3 included those with three fragility fractures. "Index fracture" was defined as the first fracture during the study period for Group 1; the second for Group 2; and the third for Group 3. Patients in each cohort and matched controls were followed for up to 60 months or until subsequent MOF (hip, vertebra, forearm, humerus), death or end of data availability. RESULTS: 231,769 women with at least one fracture were included in the study and therefore constituted Group 1; of these, 39,524 constituted Group 2 and of those, 7656 constituted Group 3. At five years, cumulative incidence of subsequent MOF was higher in patients with a history of fracture as compared to controls (Group 1: 20.7% vs 12.3%; Group 2: 32.0% vs 15.3%). Three-year cumulative incidence for Group 3 was 12.1% (vs 10.7% for controls). After adjusting for baseline covariates, risk of subsequent MOF was highest within 0-24 months following an index fracture, then decreased but remained elevated as compared to controls. Having two prior fractures, vertebral fractures and younger age at time of index fracture were associated with greater relative risk. CONCLUSIONS: Women with a history of osteoporotic fracture are at increased risk of subsequent fracture, which is highest during the first 24 months following a fracture. Younger women and those with vertebral fractures are at greatest relative risk, suggesting that treatment should target these patients and be timely enough to impact the period of imminent risk.

Differing impact of clinical factors on the risk of fracture in younger and older women in the general population and an osteoporosis clinic population.

This study assesses the impact of risk factors for fracture in women aged 80+ and 60-79. The results suggest that risk assessment which fits younger women may not be suited for the 80+ strata as many common risk factors are less predictive in the older compared to the younger cohort. PURPOSE: This study assesses whether the impact of classical risk factors for fracture due to osteoporosis is different in women aged 80+ and women aged 60-79. Since most prior research on the contribution of risk factors is based on patients below 80 years of age, this study aims to fill this knowledge gap to increase the accuracy of risk assessment in the oldest old. METHODS: Retrospective, observational cohort study using Swedish national health register data and BMD data from osteoporosis clinics. Women aged at least 60 were identified from a random sample of the general population and from the BMD databases and allocated to two populations representing patients at different stages of risk assessment. The relative impact of risk factors on fracture risk was assessed using multivariate competing risk regression with fracture as outcome and death as competing event. RESULTS: A total of 163,329 women were included from the general population (52,499 aged 80+) and 22,378 from the BMD databases (4563 aged 80+). The clinical risk factors with relatively highest effect on fracture risk in the older patients were prior fracture and hip T-score below - 2.5 SD. Other included risk factors showed lower impact in the older compared to the younger strata. CONCLUSIONS: This study confirms our understanding of the key risk factors for fracture: age, prior fracture, and a low T-score. Regarding remaining risk factors, risk assessment which fits younger women may not be suited for the 80+ strata as many common risk factors are less predictive in the older compared to the younger cohort.

Quality of life after hip, vertebral, and distal forearm fragility fractures measured using the EQ-5D-3L, EQ-VAS, and time-trade-off: results from the ICUROS.

INTRODUCTION: The International Costs and Utilities Related to Osteoporotic fractures Study is a multinational observational study set up to describe the costs and quality of life (QoL) consequences of fragility fracture. This paper aims to estimate and compare QoL after hip, vertebral, and distal forearm fracture using time-trade-off (TTO), the EuroQol (EQ) Visual Analogue Scale (EQ-VAS), and the EQ-5D-3L valued using the hypothetical UK value set. METHODS: Data were collected at four time-points for five QoL point estimates: within 2 weeks after fracture (including pre-fracture recall), and at 4, 12, and 18 months after fracture. Health state utility values (HSUVs) were derived for each fracture type and time-point using the three approaches (TTO, EQ-VAS, EQ-5D-3L). HSUV were used to estimate accumulated QoL loss and QoL multipliers. RESULTS: In total, 1410 patients (505 with hip, 316 with vertebral, and 589 with distal forearm fracture) were eligible for analysis. Across all time-points for the three fracture types, TTO provided the highest HSUVs, whereas EQ-5D-3L consistently provided the lowest HSUVs directly after fracture. Except for 13-18 months after distal forearm fracture, EQ-5D-3L generated lower QoL multipliers than the other two methods, whereas no equally clear pattern was observed between EQ-VAS and TTO. On average, the most marked differences between the three approaches were observed immediately after the fracture. CONCLUSIONS: The approach to derive QoL markedly influences the estimated QoL impact of fracture. Therefore the choice of approach may be important for the outcome and interpretation of cost-effectiveness analysis of fracture prevention.

Exploring methods for comparing the real-world effectiveness of treatments for osteoporosis: adjusted direct comparisons versus using patients as their own control.

Using Swedish and Dutch registry data for women initiating bisphosphonates, we evaluated two methods of comparing the real-world effectiveness of osteoporosis treatments that attempt to adjust for differences in patient baseline characteristics. Each method has advantages and disadvantages; both are potential complements to clinical trial analyses. PURPOSE: We evaluated methods of comparing the real-world effectiveness of osteoporosis treatments that attempt to adjust for both observed and unobserved confounding. METHODS: Swedish and Dutch registry data for women initiating zoledronate or oral bisphosphonates (OBPs; alendronate/risedronate) were used; the primary outcome was fracture. In adjusted direct comparisons (ADCs), regression and matching techniques were used to account for baseline differences in known risk factors for fracture (e.g., age, previous fracture, comorbidities). In an own-control analysis (OCA), for each treatment, fracture incidence in the first 90 days following treatment initiation (the baseline risk period) was compared with fracture incidence in the 1-year period starting 91 days after treatment initiation (the treatment exposure period). RESULTS: In total, 1196 and 149 women initiating zoledronate and 14,764 and 25,058 initiating OBPs were eligible in the Swedish and Dutch registries, respectively. Owing to the small Dutch zoledronate sample, only the Swedish data were used to compare fracture incidences between treatment groups. ADCs showed a numerically higher fracture incidence in the zoledronate than in the OBPs group (hazard ratio 1.09-1.21; not statistically significant, p > 0.05). For both treatment groups, OCA showed a higher fracture incidence in the baseline risk period than in the treatment exposure period, indicating a treatment effect. OCA showed a similar or greater effect in the zoledronate group compared with the OBPs group. CONCLUSIONS: ADC and OCA each possesses advantages and disadvantages. Combining both methods may provide an estimate of real-world treatment efficacy that could potentially complement clinical trial findings.

Swedish osteoporosis care.

The objective of this study was to review and describe the current state of Swedish osteoporosis care and to highlight ongoing challenges. This report encompasses quantitative health outcomes based on Swedish registry data as well as organizational and management aspects. Swedish osteoporosis care is characterized by a significant burden of disease, difficulties in identifying high-risk patients, and fragmented pathways for patients in need of secondary fracture prevention. This report aimed to describe the current state, gaps, and challenges in Swedish osteoporosis care, using Swedish national databases, questionnaires, and interviews with healthcare representatives. A secondary aim was to develop quality and process measures to compare differences between counties and to use those measures to describe the interaction between quantitative health outcomes and aspects of care organization and management. In conjunction with fractures, a considerably smaller proportion of men are treated than women, and a smaller proportion of older women are treated compared to younger groups. Between 3 and 16 % of patients receive treatment after a fracture, and the treatment rate in this patient group can likely increase. In addition to an unsatisfactory treatment rate, a limited number of those treated continue treatment throughout the recommended treatment durations, leading to increased risk of fracture. With a substantial variation between counties, there is a clear difficulty to identify non-persistent patients and switch to an alternative treatment. Collaboration around the patient across specialties has been lacking, and systems for secondary prevention have been concentrated to a few counties. However, when this study was conducted, there was a general trend towards implementing regional care programs. This report suggests possible strategies for improving quality of care and, hopefully, it can provide a basis for future evaluations and regional improvement of osteoporosis care in Sweden and other countries.

The comparative gastrointestinal tolerability of proprietary versus generic alendronate in patients treated for primary osteoporosis.

OBJECTIVE: The objective of this study was to analyze the comparative gastrointestinal tolerability of proprietary versus generic alendronate in patients treated for primary osteoporosis. METHODS: The study was based on all patients starting therapy with alendronate in Sweden between 2005 and 2009. The primary outcome measure was the start of treatment with a gastroprotective agent and the secondary outcome was hospitalization for gastrointestinal adverse event (GIAE). The incidence of both outcomes was measured within the first six months after the initiation of the alendronate treatment. RESULTS: The crude incidence of gastroprotective treatment during the first six months following the start of the alendronate therapy was 5.45% (bootstrapped CI(95) 4.09%-7.19%) and 5.04% (bootstrapped CI(95) 4.74%-5.38%) for patients prescribed proprietary and generic alendronate, respectively. The crude six-month incidence of hospitalization for GIAE was 0.43% (bootstrapped CI(95) 0.14%-1.29%) and 0.71% (bootstrapped CI(95) 0.55%-0.91%) for proprietary and generic alendronate, respectively. Controlling for age, sex, and other available covariates, there was no significant difference in the risk of GIAEs between proprietary and generic alendronate. CONCLUSIONS: No significant difference in the incidence of GIAEs was identified between patients prescribed proprietary and generic alendronate between 2005 and 2009 in Sweden. More research is needed to provide conclusive evidence of the gastrointestinal tolerability profiles of proprietary and generic alendronate.

Patient preferences for characteristics differentiating ovarian stimulation treatments.

BACKGROUND: Little is known concerning patient preferences for IVF treatments. The objective of this study was to elicit patient preferences for characteristics differentiating ovarian stimulation treatments. METHODS: Women undergoing IVF were recruited from six clinics in Sweden between May 2010 and December 2010. Included patients completed a study questionnaire consisting of one contingent valuation (CV) question (with six different bids) and 16 conjoint analysis (CA) questions formulated as discrete choices between two hypothetical ovarian stimulation treatments (defined in terms of manufacturing method, method of administration, time required for administration, dose variability and hypothetical price). Patient preferences were derived using multinomial logit modelling. RESULTS: The final study population consisted of 294 women (mean age of 35). Respondents were willing to pay €360 [95% confidence interval (CI): €340-€390] to receive FSH derived from DNA technology instead of highly purified extract from urine from post-menopausal women, €300 (95% CI: €280-€320) to administer the FSH using a prefilled injection pen instead of a conventional syringe, €30 (95% CI: €20-€40) per saved minute required for administration and €530 (95% CI: €500-€570) to reduce the dose variability from 10-20% to 1-2% (P< 0.001 for all estimates). The result from the CV was similar to the CA. CONCLUSIONS: Women undergoing IVF place significant value on characteristics differentiating ovarian stimulation treatments. Product-specific aspects should be taken into account by decision-makers when discriminating between commercial gonadotrophins in clinical practice to align health-care decision-making with patient preferences and potentially improve the effectiveness of IVF interventions through enhanced patient satisfaction and treatment compliance. Preferences for treatment characteristics should also be considered in evaluations of ovarian stimulation products to capture their true value from a patient perspective.

Costs related to hip disease in patients eligible for total hip arthroplasty.

This study was designed to estimate direct and indirect costs incurred by hip disease in patients eligible for total hip arthroplasty (THA). Before THA, 2635 patients completed a questionnaire regarding the use of resources because of their hip disease. Costs were assigned using official statistical sources or market prices. Annual costs amounted to US$ 7666 per patient. In a regression analysis, higher annual costs were associated with working age, female gender, comorbidity, and operation waiting time more than 90 days (P < .005). The burden of disease for THA candidates is extensive, where loss of productivity is the principal cost. Long wait for surgery is associated with increased costs. This study provides baseline cost data, which will be useful for further health economic analyses and could provide guidance for health care decision makers.

Gastrointestinal tolerability and patterns of switching in patients treated for primary osteoporosis: the Swedish Adherence Register Analysis (SARA).

The objective of this study was to describe and analyze the gastrointestinal tolerability and medication switching in patients receiving treatment for primary osteoporosis in Sweden. The study was based on all patients starting therapy with alendronate, risedronate, strontium ranelate, and raloxifene in Sweden between 2005 and 2009. The primary outcome measure was start of treatment with a gastroprotective agent, and the secondary outcome was hospitalization for a gastrointestinal adverse event (GIAE). Switching was analyzed while patients were on treatment. The crude incidence of gastroprotective treatment during the first 6 months after initiation of osteoporosis therapy was 5.14%, 5.93%, 4.25%, and 2.86% for patients prescribed alendronate, risedronate, strontium ranelate, and raloxifene, respectively. Patients prescribed raloxifene had a significantly lower risk of filling a prescription for a gastroprotective agent compared with alendronate. There was no significant difference in the risk of hospitalization for GIAEs. Less than 3% switched therapy while on treatment. Patients prescribed risedronate, strontium ranelate, and raloxifene had a significantly higher risk of switching compared with patients taking alendronate. In conclusion, no significant difference in the incidence of GIAEs was found between patients prescribed alendronate, risedronate, and strontium ranelate. Individuals prescribed raloxifene had a significantly lower risk of GIAEs compared with patients prescribed alendronate. No significant difference was found in the frequency of hospitalization for GIAEs. Switching between osteoporosis medications and drug classes was uncommon. Prescribers should consider the real-world gastrointestinal safety of osteoporosis drugs when choosing between treatment options to potentially improve medication adherence and consequently effectiveness.

The societal burden of poor persistence to treatment of osteoporosis in Sweden.

OBJECTIVES: Poor persistence to prescribed treatment regimens is a well-documented health problem. The issue is of particular importance in treatment of chronic diseases, such as osteoporosis. The objective of this study was to estimate the annual societal burden of real-world persistence to treatment of osteoporosis in Sweden. A second aim was to estimate the monetary net benefit of improved persistence. METHODS: The annual societal burden was evaluated in relation to perfect persistence to a five-year treatment duration and performed using a published Markov model by Ström and colleagues. The target population was extracted from the Swedish Prescribed Drug Register and based on all treatment-naïve patients who started therapy of primary osteoporosis in Sweden during 2009. Five hypothetical interventions were investigated, with improvements in the persistent proportion of between 10% and 50%. RESULTS: Annually, a total of 1018 fractures were estimated to be caused by non-persistence to treatment of osteoporosis in Sweden. These fractures resulted in a substantial waste of health care resources related to morbidity (€26 million annually) and a loss, in total, of 771 quality-adjusted life-years (QALYs). Using a societal willingness-to-pay for a QALY of €60000, the total annual societal burden, incorporating both monetary consequences and health effects, was estimated at €62.76 million. Given current Swedish cost-effectiveness guidelines, between approximately €225 and €1130 could be spent per patient to increase persistence, depending on the level of improvement (between 10% and 50%). CONCLUSIONS: The total annual societal burden of current, real-world persistence was estimated at €63 million. The estimated additional fracture-related costs associated with poor persistence were larger than the current total annual expenditure on all osteoporosis medications in Sweden. Poor persistence to treatment of osteoporosis should consequently be acknowledged as an important and costly health problem, and be taken into account when evaluating osteoporosis interventions.

Cost effectiveness of teriparatide and PTH(1-84) in the treatment of postmenopausal osteoporosis.

OBJECTIVES: The purpose was to assess the cost effectiveness from a societal perspective of the recombinant human parathyroid hormones: PTH(1-34) (teriparatide) and PTH(1-84) for patients with osteoporosis with similar characteristics to patients treated in normal clinical practice in Sweden. METHODS: A Markov model of osteoporosis in postmenopausal women was developed using 6-month cycles and a lifetime horizon. The model was populated with patients similar to the Swedish cohort of the European Forsteo Observational Study (postmenopausal women; mean age: 70 years, total hip T-score: -2.7 and 3.3 previous fractures). The cost effectiveness of both teriparatide and PTH(1-84) was estimated compared to no treatment and each other. Relative effectiveness assumptions were based on efficacy estimates from two phase III clinical trials. RESULTS: The cost per QALY gained of teriparatide vs. no treatment was estimated at €43,473 and PTH(1-84) was estimated at €104,396. Teriparatide was indicated to be less costly and associated with more life-years and QALYs than PTH(1-84). When assuming no treatment effect on hip fractures the cost per QALY gained was €88,379. In the sensitivity analysis the cost effectiveness did not alter substantially with changes in the majority of the model parameters except for the residual effect of the treatment after stopping therapy. CONCLUSIONS: Based on the efficacy estimates from pivotal clinical trials and characteristics of patients treated in clinical practice in Sweden, teriparatide seems to be a more cost-effective option than PTH(1-84) when compared to no treatment. The relative efficacy between the two PTH compounds was based on an indirect comparison from two separate clinical trials which has to be considered when interpreting the results.