The effect of seasonal changes and socio-economic status on urinary pH and specific gravity

Specific gravity and pH of urine in the dry and the wet season in three socio-economic Nigerian groups have been studied. Samples were collected at 7 a.m., 11 a.m. and 3 p.m. High-income subjects had a significantly lower urinary pH than low-income. During the wet season pH values were lower than in the dry, but not significantly so. During the day S.G. values did not differ, neither did they in different seasons. But there were significant differences between high and low income groups. S.G. and pH samples of high and low income groups were similar in children and in their parents. In medical students S.G. and pH in 24-hour urines were similar to the morning value of high and middle income groups and were not affected by season, but the volume was. The relevance of these findings is discussed relative to the rarity of urinary calculi in Nigerians.