Sex, menopause and chronic kidney disease in primary care

Sex differences in chronic kidney disease (CKD) are recognised, but how they change across the menopausal transition-and how this affects therapeutic opportunities in primary care-remains unclear.

We performed a cross-sectional analysis of 9 526 adults from the ONDAAS primary care study with same-day serum creatinine and urine albumin-to-creatinine ratio (ACR). eGFR was estimated with CKD-EPI 2021 and CKD classified by Kidney Disease: Improving Global Outcomes 2024 eGFR (G) and albuminuria (A) categories. Using age 50 years as a proxy for menopause, we fitted age-stratified logistic regression models for CKD G3-G5 (eGFR <60 mL/min/1.73 m²) and for A2-A3 albuminuria, and applied KDIGO 2024 criteria to estimate eligibility for renoprotective and cardioprotective therapies.

Women were 56.5% and had higher mean eGFR (84.6 vs 81.1 mL/min/1.73 m²) and lower median ACR (7.0 vs 8.3 mg/g) than men. <50 years, CKD G3 was rare in women (G3a 0.2%, G3b 0.0%); female sex reduced odds of CKD G3-G5 (aOR 0.18, 95% CI 0.05-0.69), while A2-A3 albuminuria strongly predicted CKD (aOR 33.39, 95% CI 10.41-107.13). ≥50 years, sex differences in CKD disappeared (aOR 1.01, 95% CI 0.87-1.16) and age dominated (aOR 1.13/year, 95% CI 1.12-1.14). In women ≥ 50, G3a/G3b rose to 11.3%/4.9% and G3-G4 exceeded men (17.6% vs 14.6%) despite lower A2-A3 odds (aOR 0.71, 95% CI 0.62-0.80), suggesting post-midlife eGFR-albuminuria decoupling. KDIGO 2024 eligibility in women ≥ 50: RASi 12.1%, SGLT2i 18.7%, nsMRA 3.6%, statins 35.2% (substantial opportunities even with A1-A2 albuminuria).

In this primary care population, sex differences in CKD are strongly age-dependent: women are protected before midlife, but this advantage disappears beyond age 50 years, with convergence of CKD G3-G5 risk despite differences in albuminuria. These findings support sex- and menopause-aware CKD screening and guideline-directed renoprotective and cardioprotective therapy in older women even in the absence of overt albuminuria.