Can Comorbidities Predict Gout Severity?
In addition to pain, people with gout also may have a number of other medical conditions including hypertension, cardiovascular disease, Type 2 diabetes, dyslipidemia, and renal failure. Just how gout relates to these conditions, and vice versa, is a significant grey area—but that may be changing.
Researchers in France recently performed a robust analysis of nearly 2,800 gout patients and found that patients with more than one comorbidity (such as obesity, hypertension, etc) had more severe gout.1 The authors suggested a "vicious circle" could be at play here, where comorbidities known to be risk factors for gout are further aggravated by poorly managed gout. The study was published in the Annals of the Rheumatic Diseases.
To study health of gout patients, the researchers organized the patients into 5 distinct phenotype groups based upon their comorbidity makeup (Table 1).1 These new homogenous subtypes may have revealed reciprocal links between gout and its comordities.
The researchers found that 77.7% of the patients did not meet their target serum uric acid level—hyperuricemia possibly being a risk factor for coronary heart disease, end-stage renal disease (ESRD), and even Type 2 diabetes.
One gout phenotype group, characterized with hypercholesterolemia and hypertriglyceridemia (C4), had the highest prevalence of metabolic syndrome. Liver disorders were high in this phenotype group, lending credence that high urate levels associate with cirrhosis, increased serum liver enzymes, and non-alcoholic fatty liver disease.3-5 This suggests that metabolic syndrome could instigate the onset of gout, the authors noted.
Can Gout Also Have Benefits?
While gout is associated with comorbidities and their sequelae, gout could have its own unforeseen benefits—a neuroprotective effect. Serum uric acid is known to be a powerful antioxidant and a recent case-controlled study may have evidence that gout lowers the risk of developing Alzheimer's disease (AD).6
The second study was published in the Annals of the Rheumatic Diseases.
Using a UK-based medical record database, the researchers matched non-gout individuals to gout patients by sex, age, year of enrollment, and Body Mass Index (BMI) and then calculated multivariate hazard ratios (HR), adjusting for variables and confounders, to compare the incidence rates of AD between the 2 groups.
Interestingly, univariate and multivariate HRs for senile dementia among gout patients were 0.71 and 0.76, respectively, both presenting an inverse proportion.
It's still difficult to say whether gout could have a neuroprotective benefit, though. Studies have contradicted each other. Serum acid levels may be lower in AD patients,7 potentially a novel biomarker to predict AD conversion,8 but more investigations are needed.9 By contrast, greater serum uric acid also has its own vascular risks, which could increase the risk of dementia, consequently.
The French study was funded by Ménarini and the Association Rhumatisme et Travail (Rheumatology Department, Lariboisière Hospital, Paris, France), and no conflicts of interest were reported.