Krill Oil for Knee Osteoarthritis: A Randomized Clinical Trial.

Importance: Knee osteoarthritis is disabling, with few effective treatments. Preliminary evidence suggested that krill oil supplementation improved knee pain, but effects on knee osteoarthritis remain unclear. Objective: To evaluate efficacy of krill oil supplementation, compared with placebo, on knee pain in people with knee osteoarthritis who have significant knee pain and effusion-synovitis. Design, Setting, and Participants: Multicenter, randomized, double-blind, placebo-controlled clinical trial in 5 Australian cities. Participants with clinical knee osteoarthritis, significant knee pain, and effusion-synovitis on magnetic resonance imaging were enrolled from December 2016 to June 2019; final follow-up occurred on February 7, 2020. Interventions: Participants were randomized to 2 g/d of krill oil (n = 130) or matching placebo (n = 132) for 24 weeks. Main Outcomes and Measures: The primary outcome was change in knee pain as assessed by visual analog scale (range, 0-100; 0 indicating least pain; minimum clinically important improvement = 15) over 24 weeks. Results: Of 262 participants randomized (mean age, 61.6 [SD, 9.6] years; 53% women), 222 (85%) completed the trial. Krill oil did not improve knee pain compared with placebo (mean change in VAS score, -19.9 [krill oil] vs -20.2 [placebo]; between-group mean difference, -0.3; 95% CI, -6.9 to 6.4) over 24 weeks. One or more adverse events was reported by 51% in the krill oil group (67/130) and by 54% in the placebo group (71/132). The most common adverse events were musculoskeletal and connective tissue disorders, which occurred 32 times in the krill oil group and 42 times in the placebo group, including knee pain (n = 10 with krill oil; n = 9 with placebo), lower extremity pain (n = 1 with krill oil; n = 5 with placebo), and hip pain (n = 3 with krill oil; n = 2 with placebo). Conclusions and Relevance: Among people with knee osteoarthritis who have significant knee pain and effusion-synovitis on magnetic resonance imaging, 2 g/d of daily krill oil supplementation did not improve knee pain over 24 weeks compared with placebo. These findings do not support krill oil for treating knee pain in this population. Trial Registration: Australian New Zealand Clinical Trials Registry Identifier: ACTRN12616000726459; Universal Trial Number: U1111-1181-7087.

Impact of season and geography on CompEx Asthma: a composite end-point for exacerbations.

BACKGROUND: CompEx Asthma, a novel composite end-point combining severe exacerbations (SevEx) with asthma-worsening events, was recently developed. Further characterisation of CompEx Asthma is needed to illustrate the applicability of this end-point. The objective was to evaluate CompEx Asthma as a rate end-point to determine how seasonal and geographical factors impact this novel outcome. METHODS: Seven 24-56-week randomised controlled trials of budesonide/formoterol (BUD/FORM) and benralizumab were analysed. Annualised event rates (AERs) and treatment effects (hazard ratio (HR)) were analysed with Poisson and Andersen-Gill models, respectively. Seasonality was analysed by month and five geographical regions were evaluated. RESULTS: The studies included 10 815 patients (63% female, mean age 42-49 years). CompEx Asthma AER mirrored seasonal variations in SevEx AER. CompEx Asthma AERs were higher versus SevEx in BUD/FORM and benralizumab trials (range 2.7-4.5-fold and 1.3-2.0-fold increase, respectively) and were less variable versus SevEx between regions (ratios of greatest:smallest AERs: 1.36 for CompEx versus 2.28 for SevEx (BUD/FORM); 1.81 for CompEx versus 2.22 for SevEx (benralizumab)). Treatment effects for CompEx Asthma and SevEx were generally similar across regions and months. However, in Eastern Europe, where SevEx rates were lowest, treatment effect was greater with CompEx Asthma versus SevEx, reaching statistical significance in the benralizumab studies (HR (95% CI): 0.67 (0.53-0.85) versus 0.87 (0.65-1.15)). CONCLUSION: This study confirmed the reliability of CompEx Asthma as a rate end-point and allowed detection of variations in seasonal SevEx rates, reduction of variation in rates across regions and potential greater sensitivity to treatment effects.

COPDCompEx: A novel composite endpoint for COPD exacerbations to enable faster clinical development.

BACKGROUND: Frequency of moderate and severe chronic obstructive pulmonary disease exacerbations is an important endpoint in clinical trials, but makes them large and lengthy when powered to evaluate it. We aimed to develop a composite endpoint (COPDCompEx) that could predict treatment effect on exacerbations, enabling the design of shorter early phase clinical trials requiring fewer patients. METHODS: In this post hoc analysis, data from 20 randomized controlled trials were used to develop and test COPDCompEx. Diary events were tested against predefined threshold values for peak expiratory flow, reliever medication use, and symptoms. A COPDCompEx event was defined as first occurrence of a diary event, a moderate or severe exacerbation, or a study dropout. Ratios of event frequency, treatment effect and future trial sample size were compared between COPDCompEx and moderate and severe exacerbations. FINDINGS: At 3 months, the proportion of patients experiencing COPDCompEx events increased over 3-fold versus exacerbations alone. All components contributed to COPDCompEx event rate. Treatment effects at 3 months were closely matched between COPDCompEx and exacerbations, and the large net gain in power substantially reduced the required sample size. INTERPRETATION: COPDCompEx may be used to predict treatment effect on moderate and severe exacerbations of chronic obstructive pulmonary disease. This may enable the design of shorter Phase 2 clinical trials requiring fewer patients when compared with current exacerbation studies, with exacerbations as a key Phase 3 endpoint. This would, therefore, allow more efficient decision-making with reduced burden and risk to study participants.

Urate and risk of Alzheimer's disease and vascular dementia: A population-based study.

INTRODUCTION: Low serum urate (sU) has been suggested to increase the risk of dementia since a reduction might impair antioxidant capacity. On the other hand, high sU is associated with increased cardiovascular risk which might increase the risk of dementia, especially for vascular dementia. METHODS: In 1968-1969, a population-based sample of 1462 women aged 38 to 60 years was examined and were followed up over 44 years (mean 33.1 years). We examined whether sU (determined in 1968-1969 and 1992-1994) is associated with risk of late-life dementia. RESULTS: During 44 years of follow-up, a higher sU (per standard deviation of 76.5 µmol/L) was associated with lower risk for dementia (n = 320; hazard ratio [HR] 0.81; confidence interval [CI] 0.72-0.91), Alzheimer's disease (n = 152; HR 0.78; CI 0.66-0.91), and vascular dementia (n = 52; HR 0.66; CI 0.47-0.94). DISCUSSION: Our findings support the hypothesis that sU has a protective role in the development of dementia, regardless of dementia subtype. This may have important implications in the treatment of dementia and treatment goals for hyperuricemia in patients with gout.

Medication adherence among gout patients initiated allopurinol: a retrospective cohort study in the Clinical Practice Research Datalink (CPRD).

Objectives: When urate lowering therapy is indicated in patients with gout, medication adherence is essential. This study assesses non-persistence and non-adherence in patients with newly diagnosed gout, and identifies factors associated with poor medication adherence. Methods: A retrospective data analysis was performed within the UK Clinical Practice Research Datalink (1987-2014) among incident gout patients, aged ⩾40 years and starting allopurinol (n = 48 280). The proportion of patients non-persistent (a first medication gap of ⩾90 days) after 1 and 5 years, and median time until a first 90-day gap was estimated using Kaplan-Meier statistics in those starting allopurinol and restarting after a first interruption. Non-adherence (proportion of days covered <80%) over the full observation period was calculated. Multivariable Cox- or logistic regressions assessed factors associated with non-persistence or non-adherence, respectively. Results: Non-persistence increased from 38.5% (95% CI: 38.1, 38.9) to 56.9% (95% CI: 56.4, 57.4) after 1 and 5 years of initiation. Median time until a first 90-day gap was 1029 days (95% CI: 988, 1078) and 61% were non-adherent. After a first gap, 43.3% (95% CI: 42.7, 43.9) restarted therapy within 1 year, yet only 52.3% (95% CI: 51.4, 53.1) persisted for 1 year. Being female and a current smoker increased the risk for non-persistence and non-adherence, while older age, overweight, receiving anti-hypertensive medication or colchicine and suffering from dementia, diabetes or dyslipidaemia decreased the risk. Conclusion: Medication adherence among gout patients starting allopurinol is poor, particularly among females and younger patients and patients with fewer comorbidities. Medication adherence remains low in those reinitiating after a first gap.

Medication adherence among patients with gout: A systematic review and meta-analysis.

OBJECTIVE: In the management of chronic gout, a large proportion of patients need long-term management with urate lowering therapy (ULT). This study reviews medication adherence to ULT and summarizes factors associated with adherence. METHODS: We performed a systematic literature search for studies on adherence to ULT among gout patients in PubMed, Embase, CINAHL, and PsycINFO. We conducted meta-analysis, with a random effect model, for the studies reporting the proportion of patients considered adherent to at least 80% of prescribed medication or time taken. We explored potential sources of heterogeneity, including geographic area and measure of adherence. Narrative summaries were made for data on adherence assessed/defined by Medication Event Monitoring System (MEMS)/pill-count or patient-reported, occurrence of a gap in therapy ≥30 days (non-persistence), and factors associated with adherence. RESULTS: Of the 24 studies, 16 assessed adherence using prescription/claims data, two by the MEMS or pill count, and six by patient-reported data. The pooled proportion of adherent patients (n = 13) was 46% (95% CI: 41-51); 45% across studies conducted in the USA (n = 8) and 48% in other countries (n = 5). Adherence assessed by MEMS/pill count and patient-reported was much higher than by studies using prescription/claims data. Non-persistence (n = 6) ranged from 54% to 87%. Factors associated with adherence were investigated in 18 studies. Strong evidence for a positive association with older age, more comorbidities, and the presence of diabetes or hypertension was found. CONCLUSION: Medication adherence to ULT among gout patients was poor. Better insight into reasons and consequences or poor adherence is needed.

Uric acid and blood pressure: exploring the role of uric acid production in The Maastricht Study.

OBJECTIVE: Accumulation of reactive oxygen species by increased uric acid production has been suggested as a possible underlying mechanism for the association between uric acid and high blood pressure (BP). We, therefore, investigated the association between serum uric acid concentration and 24-h urinary uric acid excretion, as proxy for uric acid production, with ambulatory 24-h blood pressure and hypertension. METHODS: Cross-sectional analyses were conducted among 2555 individuals [52% men, mean age 60.0 ±â€Š8.2 years; 27% type 2 diabetes (by design)] from The Maastricht Study. Multivariable regression analyses were performed to investigate the association of serum uric acid and 24-h urinary uric acid excretion with 24-h pulse pressure, 24-h mean arterial pressure (MAP), and hypertension. RESULTS: After adjustment for traditional hypertension risk factors, serum uric acid concentration (per SD of 81 µmol/l) was associated with higher 24-h MAP [ß 0.63 mmHg; confidence interval (CI) 0.27-1.00] and positively associated with hypertension (odds ratio 1.43; CI 1.27-1.61). Urinary uric acid excretion (per SD of 140 mg/day/1.73 m) was associated with higher 24-h MAP (ß 0.79 mmHg; CI 0.46-1.12) and with hypertension (odds ratio 1.13; CI 1.02-1.25). There was no significant association between serum and 24-h urinary uric acid excretion with 24-h pulse pressure. There was no interaction with sex or age for the aforementioned associations. CONCLUSION: Higher serum and urinary uric acid concentrations were associated with higher 24-h MAP and hypertension. These results suggest that serum and 24-urinary uric acid concentrations, the latter as proxy for uric acid production are, independent of each other, associated with BP and hypertension.

Associations of plasma uric acid and purine metabolites with blood pressure in children: the KOALA Birth Cohort Study.

OBJECTIVE: Elevated serum uric acid concentration has been associated with high blood pressure (BP) and hypertension. A putative underlying mechanism is the accumulation of reactive oxygen species when uric acid is generated by an increased enzyme activity of xanthine oxidase (XO). The aims of the present study were to investigate the associations between plasma uric acid concentration, purine metabolite ratios, as proxies for increased XO activity, and SBP and DBP in school-age children. METHODS: Cross-sectional analyses were performed in 246 children (46% boys; mean age 7.1 years) from the Dutch KOALA Birth Cohort Study. Purine metabolites were determined with ultra-performance liquid chromatography-tandem mass spectrometry. During a home visit, a nurse collected a blood sample and measured BP three times; in addition, parents measured their child's BP on three consecutive days, in the morning and evening. Generalized estimating equations were used for analyses while controlling for variables such as sex, age, BMI, physical activity, and dietary intake. RESULTS: In multivariable analysis, uric acid (per SD of 38 µmol/l) was associated with DBP z-scores [sß 0.07; confidence interval (CI), 0.01-1.14], but not with SBP z-scores. Higher ratios of uric acid/xanthine (per SD of 138) (sß 0.09; CI, 0.01-0.17) and xanthine/hypoxanthine (per SD of 321) (sß 0.08; CI, 0.02-0.17) were associated with higher DBP z-scores, but not with SBP z-scores. CONCLUSION: In school-age children, uric acid and the ratios of uric acid/xanthine and xanthine/hypoxanthine were significantly associated with DBP z-scores. Suggesting that, both uric acid concentration and increased XO activity are associated with BP.

Xanthine oxidase gene variants and their association with blood pressure and incident hypertension: a population study.

OBJECTIVE: The enzyme xanthine oxidoreductase (XOR) generates uric acid in the terminal steps of the purine metabolism; meanwhile reactive oxygen species are formed. We hypothesized that uric acid production, as assessed indirectly from XOR variants, is associated with hypertension. METHODS: Among 2769 participants (48.3% men; mean age 40.7 years) randomly recruited from European populations, we genotyped 25 tagging XOR SNPs and measured blood pressure (BP) at baseline and follow-up (median 8.8 years). The relation between variants of the XOR gene with changes in pulse pressure and mean arterial pressure over time; and incidence of hypertension, were analyzed. RESULTS: Compared with nonminor allele carriers, pulse pressure increased approximately 2 mmHg more in minor allele carriers of rs11904439 (P = 0.01), whereas mean arterial pressure and DBP increased approximately 1 mmHg less in minor allele carriers of rs2043013 (P = 0.01). In 2050, participants normotensive at baseline, hazard ratios contrasting risk of hypertension in minor allele carriers vs. nonminor allele carriers were 1.31 (95% confidence interval 1.03-1.68; P = 0.02) and 1.69 (95% confidence interval 1.11-2.57; P = 0.01) for rs11904439 and rs148756340, respectively. With the false discovery rate set at 0.25, the aforementioned associations retained significance. The changes in SBP from baseline to follow-up and the serum levels of uric acid at baseline (n = 1949) were not associated with XOR. CONCLUSION: Pending confirmation, our findings suggest that variation in uric acid production, as captured by genetic variation in XOR, might be a predictor of changes in BP and in the risk of hypertension.

Knowledge, illness perceptions and stated clinical practice behaviour in management of gout: a mixed methods study in general practice.

The objective of the present study is to explore knowledge, illness perceptions and stated practice behaviour in relation to gout in primary care. This is a mixed methods study among 32 general practitioners (GPs). The quantitative assessment included the Gout Knowledge Questionnaire (GKQ; range 0-10; better) and Brief Illness Perceptions Questionnaire (BIPQ; nine items, range 0-10; stronger). Structured individual interviews obtained further qualitative insight into knowledge and perceptions, in the context of daily practice. Among 32 GPs, 18 (56.3 %) were male, mean age 44.4 years (SD 9.6) and mean working experience 17.1 years (SD 9.7). Median score [interquartile ranges (IQR)] on the GKQ was 7.8 [6.7-8.9] and 9.0 [8.0-10.0], when presented as open or multiple-choice questions, respectively. The BIPQ (median; [IQR]) revealed that gout was seen as a chronic disease (8.0; [7.0-9.0]), affecting life and emotions moderately (6.5; [5.0-7.0]), having many severe symptoms (8.0; [7.0-9.0]) and in which treatment could be very helpful (8.0; [7.0-9.0]). Further interviews revealed large variation in specific aspects of knowledge and about gaps concerning indications for uric acid-lowering therapy (UALT), duration of UALT, target serum uric acid (sUA) level or duration of prophylactic treatment. Finally, patients' adherence was not checked systematically. Specific knowledge gaps and discrepancies between perceptions and stated practice behaviour were identified, which might hamper effective management of this well-treatable disease. Improving evidence on the rationale and effectiveness of treatment targets and adherence interventions, tailoring guidelines to general practice and intensification of implementation of guidelines in primary health care seem to be needed.