Trends in the Pattern of Leukaemia Incidence in a Tertiary Health Center in Nigeria: 1990-2004

Leukaemia is an important cause of morbidity and mortality in Nigeria. The aim of this study is to determine the incidence and trend in the pattern of adult leukaemia over a period of 15 years in Benin City, Nigeria. The case records of 253 cases that attended the University of Benin Teaching Hospital, Benin City, Nigeria from 1990-2004 with a diagnosis of leukaemia were analyzed. Chronic myeloid leukaemia (CML) was the more frequent variety (27.7%), followed by chronic lymphocytic leukaemia (CLL) and prolymphocytic leukaemia (PLL) with equal proportions of 21.3% each. Time trend analysis by 5-year calendar periods revealed an increasing number and incidence of patients with leukaemia. There was also an increased incidence of leukaemia among the youths (21-40years) whereas that of the older patients (61-70years) has decreased. There was a statistically significant association between age and number of leukaemia cases at presentation for the various years (P = 0.023). A positive correlation with a significant linear trend was also obtained (r = 0.3507; P = 0.0048) such that there was a predominance of young patients (21-40 years) in latter years (2000-2004) compared to a decline in the older patients (> 60 years) for the period studied. There was increased incidence of leukaemia especially among the younger age groups.