Objective: To determine the morbidity and mortality related to respiratory diseases among adults attending a tertiary-care hospital in Nigeria. Methods: We carried out a retrospective study of 183 adult patients (> 15 years of age), diagnosed with respiratory diseases between November of 2006 and October of 2008 at the Federal Medical Centre in Ido-Ekiti, Nigeria. Results: Of the 183 patients enrolled in the study, 78 (42.6%) were male and 105 (57.4%) were female, the male:female ratio being 1:1.4. Respiratory diseases were predominant in the 25-44 year age bracket (37.2%) and lower socioeconomic class (81.4%). Pulmonary TB was the leading cause of morbidity (in 42.1%), followed by asthma (in 17.5%) and pneumonia (in 15.3%). Lung cancer was uncommon (in only 0.6%). Pulmonary TB was the leading cause of hospitalization for respiratory disease (in 32%). Pulmonary TB, asthma, pneumonia and pleural pathologies were more common in women, whereas COPD was more common in men. The most common comorbidity was HIV infection (in 11.5%). The overall mean length of hospital stay was 14 days. Overall mortality was 8.7%; 50% of the deaths were attributed to pulmonary TB, 25% were attributed to pleural disease, 12.5% were attributed to pneumonia, and 6.25% were attributed to acute exacerbation of COPD. Mortality was higher in women and in the 25-44 year age bracket. Conclusions: Pulmonary TB, asthma and pneumonia were the leading causes of respiratory disease-related morbidity. Pulmonary TB was the leading cause of respiratory disease-related mortality among the adult Nigerians evaluated. Therefore, these conditions should be given higher priority in patient care. In addition, antiretroviral therapy should be readily accessible and affordable to HIV-infected individuals.Keywords: Morbidity; Mortality; Respiratory tract diseases; Africa. ResumoObjetivo: Determinar a morbidade e a mortalidade relacionadas a doenças respiratórias em adultos atendidos em um hospital terciário na Nigéria. Métodos: Estudo retrospectivo com 183 pacientes adultos (> 15 anos) diagnosticados com doenças respiratórias, entre novembro de 2006 e outubro de 2008, no Centro Médico Federal em Ido-Ekiti, Nigéria. Resultados: Dos 183 pacientes estudados, 78 (42,6%) eram do sexo masculino e 105 (57,4%) do sexo feminino (razão entre homens e mulheres: 1:1,4). As doenças respiratórias foram predominantes na faixa etária entre 25 e 44 anos (37,2%) e classe socioeconômica baixa (81,4%). A forma pulmonar da TB foi a principal causa de morbidade (em 42,1%), seguida por asma (em 17,5%) e pneumonia (em 15,3%). O câncer de pulmão foi raro (em somente 0,6%). A TB pulmonar foi a principal causa de hospitalização devido à doença respiratória (em 32%). A forma pulmonar da TB, asma, pneumonia e patologias da pleura foram mais frequentes no sexo feminino, ao passo que a DPOC foi mais frequente no sexo masculino. A comorbidade mais frequente foi a infecção por HIV (em 11,5%). A média do tempo de hospitalização foi de 14 dias. A mortalidade foi 8,7%; 50% das mortes foram ...