The association of gout with sleep disorders: a cross-sectional study in primary care

[Diurnal differences in acute gout attacks: A clinical study of male gout patients]

OBJECTIVE

To observe the diurnal difference of acute gout attacks in men, and provide reference for accurate clinical prevention and treatment.

METHODS

Using a single-center, cross-sectional study design, the patients diagnosed with gout in the outpatient department of Rheumatology and Immuno-logy of PLA Joint Logistic Support Force No.980 Hospital from October 2021 to April 2022 were selected. The information about the patient's current/last acute gout attacks (less than 2 weeks from visit), date and time of attacks, joint symptoms and signs, medication use, and relevant biochemical tests on the day of visit was recorded. The diurnal time difference of acute gout attacks in male patients was analyzed, and univariate comparison and multivariate Logistic regression analyses were conducted to compare the diurnal difference of acute gout attacks with clinical characteristics and biochemical indicators.

RESULTS

A total of 100 male gout patients were included, and 100 acute attacks were recorded. Diurnal distribution of acute gout attacks: morning (6:00~11:59, 18, 18%), afternoon (12:00~17:59, 11, 11%), the first half of the night (18:00~23:59, 22, 22%), the second half of the night (0:00~05:59, 49, 49%); During the day (included morning and afternoon, 29, 29%) and at night (included the first half of the night and the second half of the night, 71, 71%). The rate of acute gout attack was significantly higher at night than in the day (about 2.5 ∶1). No matter the first or recurrent gout, no matter the duration of the disease, the number of acute gout attacks had the difference of less in the day and more in the night. Serum urate (SU) level was higher in the patients with nocturnal attack than in those with daytime attack (P=0.044). Comorbidities were significantly different in the day-night ratio of the number of acute gout attack (P=0.028). Multiple Logistic regression analysis showed that SU level (OR=1.005, 95%CI: 1.001-1.009) and comorbidities (OR=3.812, 95%CI: 1.443-10.144) were the correlative factors of nocturnal acute gout attacks.

CONCLUSION

No matter the first or recurrent gout, no matter the duration of the disease, it has a diurnal variation characterized by multiple attacks at night, increased SU level and comorbidities are correlative factors for nocturnal acute attack of gout.

Assessing the causal associations of obstructive sleep apnea with serum uric acid levels and gout: a bidirectional two-sample Mendelian randomization study

OBJECTIVE

Multiple observational studies have reported the close associations of obstructive sleep apnea (OSA) with serum uric acid (SUA) levels and gout. However, the causal nature and direction remains unclear.

METHODS

A bidirectional two-sample Mendelian randomization (MR) study was performed, based on publicly available genome-wide association studies (GWAS) summary statistics, to investigate whether OSA is causally related to SUA levels, gout and vice versa. The inverse-variance weighted (IVW) was used as the primary analysis approach, supplemented with four sensitive analysis methods applied to assess the robustness of the results. Moreover, multivariable MR (MVMR) was utilized to evaluate the independent causal effect of OSA on SUA and gout after adjusting for body mass index (BMI), hypertension, type 2 diabetes (T2D), coronary artery disease (CAD), and chronic kidney disease (CKD).

RESULTS

Genetically predicted OSA liability was significantly associated with increased levels of SUA (IVW method: β = 0.19, 95% CI = 0.11 - 0.26, P = 7.24 × 10^-7) and risk of gout [IVW method: odds ratio (OR) = 1.75 95% CI = 1.13 - 2.69, P = 0.01] in univariable MR. The MVMR results suggested that OSA retained its significant association with increased SUA levels, whereas the significant association between OSA and gout was attenuated to null after adjusting for BMI and T2D. No causal effect of OSA on SUA levels and gout was found in the reverse direction.

CONCLUSIONS

Our findings suggest that OSA was causally associated with increased levels of SUA, but was not independently associated with gout risk.

Chronobiology and Chronotherapy in Inflammatory Joint Diseases

Circadian rhythm perturbations can impact the evolution of different conditions, including autoimmune diseases. This narrative review summarizes the current understanding of circadian biology in inflammatory joint diseases and discusses the potential application of chronotherapy. Proinflammatory cytokines are key players in the development and progression of rheumatoid arthritis (RA), regulating cell survival/apoptosis, differentiation, and proliferation. The production and secretion of inflammatory cytokines show a dependence on the human day–night cycle, resulting in changing cytokine plasma levels over 24 h. Moreover, beyond the circadian rhythm of cytokine secretion, disturbances in timekeeping mechanisms have been proposed in RA. Taking into consideration chronotherapy concepts, modified-release (MR) prednisone tablets have been introduced to counteract the negative effects of night-time peaks of proinflammatory cytokines. Low-dose MR prednisone seems to be able to improve the course of RA, reduce morning stiffness and morning serum levels of IL-6, and induce significant clinical benefits. Additionally, methotrexate (MTX) chronotherapy has been reported to be associated with a significant improvement in RA activity score. Similar effects have been described for polymyalgia rheumatica and gout, although the available literature is still limited. Growing knowledge of chronobiology applied to inflammatory joint diseases could stimulate the development of new drug strategies to treat patients in accordance with biological rhythms and minimize side effects.

Gout and risk of diabetes mellitus: meta-analysis of observational studies

To determine the prevalence of diabetes mellitus (DM) in people with gout, and investigate the relationship between gout and the occurrence of DM. Systematic review and meta-analysis of epidemiological studies. Data sources: MEDLINE, Web of Science, EMBASE and CINAHL databases, hand-searched reference lists, citation history and contact with authors. Eligibility criteria: cohort, case-control or cross-sectional studies which examined the occurrence of DM amongst adults with gout (with or without gout group) in primary care or general population samples. Prevalence and risk estimate meta-analyses were performed using a random-effects model. A total of 23 identified studies matched the inclusion criteria, reporting on a total of 575 284 gout patients. Meta-analyses revealed that the prevalence of DM in gout patients was 16% (95% CI, 14-18%, I² = 99.8%) according to clinical interviews. In the subgroup analysis, the prevalence of DM was higher in the female population (18%, 95%CI 2.7-33.3%) than the male population (12.6%, 95%CI 8.2-17.1%). As age increased, the incidence of diabetes in gout population increased. DM is commonly found among patients with gout. Patients with gout should be actively screened for DM and its consequences.

A meta-analysis of the association between gout, serum uric acid level, and obstructive sleep apnea

Previous epidemiological investigations have evaluated the association between gout, serum uric acid levels, and obstructive sleep apnea syndrome (OSAS), but with inconsistent results. We conducted this meta-analysis aiming at providing clear evidence about whether OSAS patients have higher serum uric acid levels and more susceptible to gout. Relevant studies were identified via electronic databases from inception to December 17, 2018. Study selection was conducted according to predesigned eligibility criteria, and two authors independently extracted data from included studies. The hazard ratio (HR) and weighted mean difference (WMD) and their corresponding 95% confidence interval (CI) were derived using random-effects models. We conducted meta-, heterogeneity, publication bias, sensitivity, and subgroup analyses. Eighteen studies, involving a total of 157,607 individuals (32,395 with OSAS, 125,212 without OSAS) and 12,262 gout cases, were included. Results show that serum uric acid levels are elevated in patients with OSAS (WMD = 52.25, 95% CI 36.16-64.33); OSAS did not reach statistical significance as a predictor of gout (but there was a trend, HR = 1.25, 95% CI 0.91-1.70) and that the association between OSAS and serum uric acid was quite robust. OSAS may be a potential risk factor for hyperuricemia and the development of gout and thus, effective OSAS therapy may present as a valuable preventive measure against gout. Still, it is vital to undertake clinical studies with better designing to corroborate these associations and shed new light on it.

Self-reported sleep quality and sleep disorders in people with physician-diagnosed gout: an Internet cross-sectional survey

Background

Limited information exists regarding sleep disorders in gout. Our objective was to assess the burden of sleep disorders in people with gout.

Methods

A brief anonymized Internet survey of people with physician-diagnosed gout who visited a gout education website assessed the frequency of sleep problems, sleep quality over the past 24 h (0 = best possible sleep, 10 = worst possible sleep), daytime sleepiness on a typical day (0 = none and 10 = most sleepy during the day), sleep quantity (number of hours of sleep), and the frequency of snoring or gasping, and snorting or stopping breathing during the sleep, using validated questionnaires, including the NHANES 2016 sleep questionnaire. We used Chi-square test to compare the categorical and t test the continuous variables.

Results

Of the 454 website visitors who clicked the survey, 320 survey respondents reported physician-diagnosed gout. Mean age was 57 years (standard deviation [SD], 13.4), 72% were male, 77% were White, and mean gout duration was 7.6 (SD, 11). Of the respondents, 23% reported doctor-diagnosed sleep disorder (sleep apnea, 17%; sleep study ordered, diagnosis pending, 4%; other sleep disorder 2%). A mean 6.7 h of sleep per night was reported (SD, 1.3). Eighty-six percent reported snoring during sleep and 45% reported having snorted, gasped, or stopped breathing while asleep. Two thirds of the patients reported feeling sleepy during the day, at least 3–4 times a month or more. Sleep quality was 5.5 (SD, 2.6), and daytime sleepiness was 3.5 (SD, 2.6) on a 0–10 scale (higher = worse).

Conclusions

People with physician-diagnosed gout reported frequent sleep disorders and daytime sleepiness in an Internet survey. More in-depth studies are needed to better understand the association of gout with sleep disorders.

Social support and post-traumatic growth among a sample of arthritis patients: Analysis in light of conservation of resources theory

The study examined the association between social support dimensions and post-traumatic growth (PTG) among a sample of arthritis patients. In particular, we wanted to verify the mediating role of resources, as described by the Conservation of Resources (COR) theory, on the aforementioned relationship. A total of 207 patients with a clinical diagnosis of arthritis were recruited to participate in the study, including 149 females and 58 males. This was a cross-sectional study, with PTG evaluated by the Post-Traumatic Growth Inventory (PTGI) and social support assessed via the Berlin Social Support Scales (BSSS). To assess the level of subjectively possessed resources among participants, we used the COR evaluation questionnaire (COR-E). Provided support, but not received support, was positively related to the level of PTG among participants. In addition, the level of spiritual resources mediated the aforementioned relationship. The results of this contribute to the literature on the psychological aspects of arthritis. It seems that providing support may be related to positive consequences among arthritis patients, in the form of PTG, with spiritual resources being of significant value in this process.

The Risk of Gout Among Patients With Sleep Apnea: A Matched Cohort Study

OBJECTIVE

Obstructive sleep apnea (OSA) is associated with a range of serious comorbidities. This study was undertaken to investigate whether people with OSA are more likely to develop gout, in the short and long term, compared to those without OSA.

METHODS

A matched retrospective cohort study was undertaken using the UK Clinical Practice Research Datalink. Individuals age ≥18 years who received a diagnosis of OSA between 1990 and 2010 were identified and matched on age, sex, and practice with up to 4 individuals without OSA; follow-up was until the end of 2015. Hazard ratios (HRs) were estimated using Cox regression adjusted for general health, lifestyle, and comorbidity characteristics. The risk of developing gout was assessed at different time points, and the body mass index (BMI) category-specific results were presented.

RESULTS

The study sample included 15,879 patients with OSA and 63,296 without. The median follow-up was 5.8 years. We found that 4.9% of patients with OSA and 2.6% of patients without the disorder developed gout. The incidence rate per 1,000 person-years was 7.83 (95% confidence interval [95% CI] 7.29-8.40) and 4.03 (95% CI 3.84-4.23) among those with and without OSA, respectively. The adjusted HR was 1.42 (95% CI 1.29-1.56). The risk of developing gout among OSA patients compared to those without was highest 1-2 years after the index date (HR 1.64 [95% CI 1.30-2.06]). This finding persisted among those who were overweight and obese. For those with normal BMI, the highest significant HR (2.02 [95% CI 1.13-3.62]) was observed at 2-5 years after the index date.

CONCLUSION

In this study, patients with OSA continued to be at higher risk of developing gout beyond the first year following the diagnosis. Our results further indicate that peak incidences of gout vary according to BMI.

Diabetes mellitus and arthritis: is it a risk factor or comorbidity?: A systematic review and meta-analysis

BACKGROUND

Investigators have explored the association between diabetes mellitus and arthritis for a long time; however, there are uncertainties and inconsistencies among various studies. In this study, we tried to explore the relationship between diabetes mellitus and the overall risk of arthritis, as well as the potential modifiers for this relationship.

METHODS

We conducted a comprehensive literature search through PubMed and identified 36 eligible studies. The overall analyses, subgroup analyses, as well as sensitivity analyses, were conducted to illustrate the association between diabetes mellitus and arthritis. Study quality was evaluated using the Newcastle-Ottawa Quality Assessment Scale. All statistical analyses were conducted using STATA SE version 13.0.

RESULTS

In our study, 36 eligible studies were identified and involved in the meta-analysis. The overall association between diabetes mellitus and arthritis is 1.61 (95% confidence interval [CI]: 1.14-2.28, P = .007). The association exists only in nongouty arthritis, where we observed the estimated odds ratio (OR) 1.33 (95% CI: 1.05-1.67, P < .001). The opposite point estimates from different types of diabetes may indicate possible different associations for type I (OR: 0.98, 95% CI: 0.18-5.39, P = .985) or type II diabetes (OR: 1.28, 95% CI: 0.88-1.84, P = .194).

CONCLUSION

Diabetes mellitus performs more likely as a comorbidity of arthritis rather than a risk factor; however, more studies will be helpful to increase the confidence of identifying the association between diabetes and arthritis.

Sleep Apnea and the Risk of Incident Gout: A Population-Based, Body Mass Index-Matched Cohort Study

OBJECTIVE

Sleep apnea is associated with hyperuricemia owing to hypoxia-induced nucleotide turnover. We undertook this study to assess the relationship between incident sleep apnea and the risk of incident gout.

METHODS

Using data from The Health Improvement Network in the UK, we identified individuals with a first-ever physician diagnosis of sleep apnea. For each patient with sleep apnea, up to 5 individuals without sleep apnea were matched by sex, age, birth year, and body mass index (within ±0.5 kg/m(2) ). We estimated the incidence rates of gout and examined the relationship between sleep apnea and the risk of incident gout using a Cox proportional hazards model, adjusting for potential confounders. In addition, we assessed the rate difference in gout due to sleep apnea using an additive hazard model.

RESULTS

Among 9,865 patients with newly diagnosed sleep apnea and 43,598 matched individuals without sleep apnea, we identified 270 incident cases of gout over 1 year of followup, resulting in incidence rates of 8.4 per 1,000 person-years and 4.8 per 1,000 person-years, respectively. The crude and multivariable rate ratios of incident gout in patients with sleep apnea were 1.7 (95% confidence interval [95% CI] 1.3, 2.2) and 1.5 (95% CI 1.1, 2.1), respectively. The corresponding rate differences between patients with sleep apnea and the comparison cohort were 3.6 (95% CI 1.6, 5.6) and 2.8 (95% CI 0.7, 4.9) per 1,000 person-years. The effect of sleep apnea persisted across subgroups.

CONCLUSION

This general population-based study indicates that sleep apnea is independently associated with an increased risk of incident gout. Future research should examine the potential benefits of correcting sleep apnea-induced hypoxia on the risk of hyperuricemia and gout flares.

Nonapnea Sleep Disorders in Patients Younger than 65 Years Are Significantly Associated with CKD: A Nationwide Population-Based Study

Background

Nonapnea sleep disorders (NASD) and sleep-related problems are associated with poor health outcomes. However, the association between NASD and the development and prognosis of chronic kidney disease (CKD) has not been investigated thoroughly. We explored the association between CKD and NASD in Taiwan.

Methods

We conducted a population-based study using the Taiwan National Health Insurance database with1,000,000 representative data for the period from January 1, 2000 to December 31, 2009. We investigated the incidence and risk of CKD in 7,006 newly diagnosed NASD cases compared with 21,018 people without NASD matched according to age, sex, index year, urbanization, region, and monthly income at a 1:3 ratio.

Results

The subsequent risk of CKD was 1.48-foldhigher in the NASD cohort than in the control cohort (95% confidence interval [CI] = 1.26–1.73, p< 0.001). Men, older age, type 2 diabetes mellitus, and gout were significant factors associated with the increased risk of CKD (p< 0.001). Among different types of NASDs, patients with insomnia had a 52% increased risk of developing CKD (95%CI = 1.23–1.84; P<0.01), whereas patients with sleep disturbance had a 49%increased risk of subsequent CKD (95% CI = 1.19–1.87; P<0.001). Younger women (aged < 65 years) were at a high risk of CKD with NASD (adjusted hazard ratio, [HR] = 1.81; 95% CI = 1.35–2.40, p< 0.001).

Conclusions

In this nationwide population-based cohort study, patients with NASD, particularly men of all ages and women aged younger than 65 years, were at high risk of CKD.

Serum urate and obstructive sleep apnoea in severe obesity

Obstructive sleep apnoea (OSA) may increase the risk of hyperuricaemia and predispose to gout. The evidence for the effects of OSA on serum urate in severe obesity is limited. This study investigated whether OSA was associated with serum urate in severe obesity and whether continuous positive airway pressure (CPAP) treatment was associated with a fall in urate. Severely obese subjects without known OSA or gout were recruited. Baseline assessments included urate, metabolic parameters, spirometry and overnight polysomnography. OSA patients were initially naive to treatment and were offered CPAP. At follow-up, change in urate was compared between CPAP-treated and non-CPAP-treated subjects. A high urate was defined as greater than the median. Logistic regression was performed to identify associations between (1) OSA and high urate at baseline and (2) use of CPAP and change in urate at follow-up. In total, 92 subjects were recruited (61 (66%) OSA and 31 (34%) non-OSA). Median urate was 345 μmol/L. OSA was associated with high urate in females at baseline after adjusting for confounders (adjusted odds ratio ORadj = 10.2; 95% CI: 1.1, 93.5). At follow-up (14 months), 58 subjects (28 on CPAP and 30 not on CPAP) were reassessed. CPAP was significantly associated with a fall to a low urate category at follow-up ( = 0.017). Regression revealed a trend for a fall in urate category in the CPAP-treated group (ORadj = 9.3; 95% CI: 0.8, 97). Serum urate is associated with OSA in severely obese females and CPAP may reduce levels in patients with OSA. There may be a need to consider and assess for OSA in obese patients with hyperuricaemia and recurrent attacks of gout.

Nocturnal risk of gout attacks

OBJECTIVE

Several plausible mechanisms and anecdotal descriptions suggest that gout attacks often occur at night, although there are no scientific data supporting this. We undertook this study to evaluate the hypothesis that gout attacks occur more frequently at night.

METHODS

We conducted a case-crossover study to examine the risk of acute gout attacks in relation to the time of the day. Gout patients were prospectively recruited and followed up via the internet for 1 year. Participants were asked about the following information concerning their gout attacks: the date and hour of attack onset, symptoms and signs, medication use, and purported risk factors during the 24- and 48-hour periods prior to the gout attack. We calculated the odds ratios (ORs) of gout attacks (with 95% confidence intervals [95% CIs]) according to three 8-hour time blocks of the day (i.e., 12:00 AM to 7:59 AM, 8:00 AM to 3:59 PM [reference], and 4:00 PM to 11:59 PM) using conditional logistic regression.

RESULTS

Our study included 724 gout patients who experienced a total of 1,433 attacks (733, 310, and 390 attacks during the first, second, and third 8-hour time blocks, respectively) over 1 year. The risk of gout flares in the 8-hour overnight time block (12:00 AM to 7:59 AM) was 2.36 times higher than in the daytime (8:00 AM to 3:59 PM) (OR 2.36 [95% CI 2.05-2.73]). The corresponding OR in the evening (4:00 PM to 11:59 PM) was 1.26 (95% CI 1.07-1.48). These associations persisted among those with no alcohol use and in the lowest quintile of purine intake in the 24 hours prior to attack onset. Furthermore, these associations persisted in subgroups according to sex, age group, obesity status, diuretic use, and use of allopurinol, colchicine, and nonsteroidal antiinflammatory drugs.

CONCLUSION

These findings provide the first prospective evidence that the risk of gout attacks during the night and early morning is 2.4 times higher than in the daytime. Further, these data support the purported mechanisms and historical descriptions of the nocturnal onset of gout attacks and may have implications for antigout prophylactic measures.

Obstructive sleep apnea syndrome: An important piece in the puzzle of cardiovascular risk factors

The obstructive sleep apnea syndrome (OSA) is a clinical entity characterized by recurring episodes of apnea and/or hypopnea during sleep, due to a total or partial collapse, respectively, of the upper airway. This collapse originates a set of pathophysiological changes that determine the appearance of several cardiovascular complications. OSA contributes for the development of hypertension, heart failure, arrhythmias and coronary heart disease. Nowadays it is recognized to be an important public health problem, taking into account not just its repercussions but also its prevalence, since the main risk factor for the disease is obesity, a growing problem worldwide, both in developed and developing countries. The present review summarizes the current knowledge about OSA, as regards its definition, pathophysiology, clinical manifestations, diagnosis, cardiovascular effects and treatment.

Epidemiology of gout

Gout is the most prevalent inflammatory arthritis in men. The findings of several epidemiologic studies from a diverse range of countries suggest that the prevalence of gout has risen over the past few decades. Although incidence data are scarce, data from the United States suggests that the incidence of gout is also rising. Evidence from prospective epidemiologic studies has confirmed dietary factors (animal purines, alcohol, and fructose), obesity, the metabolic syndrome, hypertension, diuretic use, and chronic kidney disease as clinically relevant risk factors for hyperuricemia and gout. Low-fat dairy products, coffee, and vitamin C seem to have a protective effect.