Adipokine genes and radiographic hand osteoarthritis in Finnish women: a cross-sectional study

Abstract

Objectives: Available evidence suggests that genetic factors and overweight play major roles in the aetiology of osteoarthritis (OA). We analysed the association of 18 single-nucleotide polymorphisms (SNPs) from nine adipokine and adipokine receptor genes (LEP, LEPR, ADIPOQ, RETN, NAMPT, SERPINA12, ITLN1, RARRES2, and APLN) with radiographic hand OA.

Method: The study design was cross-sectional. Bilateral hand radiographs of 542 occupationally active Finnish female dentists and teachers aged 45–63 years were examined and classified for the presence of hand OA using reference images. Hand OA was defined as at least three finger joints with radiographic OA of grade 2–4. The genotypes were determined using polymerase chain reaction-based methods. Body mass index (BMI) was calculated based on self-reported height and measured weight. Associations of the individual SNPs and their haplotypes with hand OA were tested using logistic regression analysis.

Results: The minor allele of RETN rs10401670 was associated with a decreased [odds ratio (OR) = 0.73, 95% confidence interval (CI) 0.55–0.97, p = 0.03] and RARRES2 rs4721 with an increased (OR 1.41, 95% CI 1.07–1.87, p = 0.01) prevalence of hand OA. Also, LEPR AC (OR 1.54, 95% CI 1.01–2.35, p = 0.05) and RETN GGTT (OR 0.58, 95% CI 0.37–0.93, p = 0.02) haplotypes were associated with hand OA. These associations were modified by BMI when comparing normal and overweight women. However, the associations lost their statistical significance after adjusting for multiple testing.

Conclusion: Our results suggest weak associations between the studied variations in LEPR, RARRES2, and RETN genes and hand OA in Finnish women, and that the associations are modified by BMI. However, these associations could not be verified in the current study.

Acknowledgements

We are grateful to Katariina Luoma MD (University of Helsinki, Helsinki University Central Hospital, Radiology Department, Finland) for performing the second readings of the hand radiographs for reliability analysis. We thank Tanja Katovich for the help in genotyping analyses.

The study was financially supported by a grant from the Finnish Work Environment Fund [101334] and a grant from National Doctoral Programme of Musculoskeletal Disorders and Biomaterials (TBDP).

Additional information

Funding

This work was supported by the Finnish Work Environment Fund [101334];National Doctoral Programme of Musculoskeletal Disorders and Biomaterials;