Population Impact Attributable to Modifiable Risk Factors for Hyperuricemia

Abstract

Objective: To examine modifiable risk factors in relation to the presence of hyperuricemia and to estimate the proportion of hyperuricemia cases in the general population that could be prevented by risk factor modification, along with estimates of the variance explained.

Methods: Using data obtained from 14,624 adults representative of the US civilian noninstitutionalized population, we calculated adjusted prevalence ratios for hyperuricemia, population attributable risks (PARs), and the variance explained according to the following 4 factors: body mass index (BMI; ≥25 kg/m² ), alcohol intake, nonadherence to a Dietary Approaches to Stop Hypertension (DASH) diet, and diuretic use.

Results: BMI, alcohol intake, adherence to a DASH-style diet, and diuretic use were all associated with serum urate levels and the presence of hyperuricemia in a dose-dependent manner. The corresponding PARs of hyperuricemia cases for overweight/obesity (prevalence 60%), nonadherence to a DASH-style diet (prevalence 82%), alcohol use (prevalence 48%), and diuretic use (prevalence 8%) were 44% (95% confidence interval [95% CI] 41%, 48%), 9% (95% CI 3%, 16%), 8% (95% CI 5%, 11%), and 12% (95% CI 11%, 14%), respectively, whereas the corresponding variances explained were 8.9%, 0.1%, 0.5%, and 5.0%. Our simulation study showed the variance nearing 0% as exposure prevalence neared 100%.

Conclusion: In this nationally representative study, 4 modifiable risk factors (BMI, the DASH diet, alcohol use, and diuretic use) could be used to individually account for a notable proportion of hyperuricemia cases. However, the corresponding serum urate variance explained by these risk factors was very small and paradoxically masked their high prevalences, providing real-life empirical evidence for its limitations in assessing common risk factors.

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Population Attributable Risk vs Variance Explained According to the Prevalence of Diuretic Use

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Population Attributable Risk vs Variance Explained According to the Prevalence of Alcohol Use

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Causal Pathways of Modifiable Factors (Diet and Physical Activity) on Developing Hyperuricemia (HU). Input (diet) and output (physical activity) of calories are the modifiable determinants of overweight/obesity, which leads to HU (indirect effect mediated by overweight/obesity). The other causal pathway for HU is a direct effect, not mediated by overweight/obesity (e.g., isocaloric DASH diet or Western diet not affecting weight). The total effect of these lifestyle modifications is the combination of indirect and direct effects. Consistent with the large role of overweight/obesity on the risk of HU, published papers suggest that the indirect effect of these lifestyle factors (through overweight/obesity) is larger than their direct effect.(46,47) CVD = cardiovascular disease, T2D = type-2 diabetes, CKD = chronic kidney disease.