ABSTRACT
AIM: The aim of the present study was to assess the trajectories of glomerular filtration rate (GFR) and determinants of change during a 3-year period in free-living mixed-ancestry South Africans. METHODS: In all 320 (78.1% women) adults, aged 56.2 years, from Cape Town were examined in 2008 and 2011. Estimated glomerular filtration rate (eGFR) was based on the Modification of Diet in Renal Disease model; and staging of eGFR used the National Kidney Foundation's classification. RESULTS: Mean eGFR (mL/min per 1.73 m2) was 68.6 at baseline and eGFR stages were: > 90 (9.4%), 60-90 (58.7%), 30-60 (28.1%) and < 30 (0.9%). eGFR increased by 8 mL/min during follow-up, reflecting variable trajectories by baseline eGFR stages, sex, hypertension and glucose tolerance (all P-interaction ≤ 0.012). Movements across eGFR stages during follow-up favoured improvement in 113 participants (35.3%), and worsened in 23 (7.2%). In adjusted multinomial logistic regressions, men had a 72% (43-86%) lower chance of improvement, while each mmHg higher systolic blood pressure conferred a 7% (3-11%) risk of deterioration. Equivalent for each 1% HbA1c was 30% (8-56%). Participants with glucose intolerance had 102% (3-297%) higher chances of improvement than diabetics. CONCLUSION: Variable trajectories of eGFR with time were observed in this cohort, reflecting the effects of modifiable risk factors such as hypertension and dysglycaemia.