Expenditure and Quality of Life Lost Due to Diseases Caused by Smoking	Objective: To evaluate the expense and quality of life of patients with obstructive pulmonary disease and coronary heart disease, their associated factors, and to estimate the economic and quality of life lost among these patients. 	Methods: Analytic cross-sectional study was conducted in 5 regions all over Thailand, Chiang Mai representing the northern region, Khonkaen the north-eastern, Chonburi the eastern region, Songkhla the southern region, and Bangkok including the outer skirt. The study population included male and female patients with clinical diagnoses of obstructive pulmonary disease or coronary heart disease, who self reportedly had smoked for at least 5 years (in the case of coronary heart disease) or 10 years (in the case of obstructive pulmonary disease), and who attended the hospitals as the out-patients or being admitted as the in-patients during the study period. The comparison group comprised of the general people or persons who accompanied patients to hospitals, who did not have any chronic diseases or disabilities. They were matched with the patients according to gender, age and place of residency. Data were collected between June and December 1998, by using a standard questionnaire and a record form containing questions on personal and sociodemographic characteristics, history of smoking and of the disease, direct and indirect medical costs and indirect costs. The WHOQOL-BREF quality of life assessing instrument was used to measure the subject’s quality of life. Data were presented with descriptive statistics. The patient’s expense and the quality of life lost compared to the compariron group were analysed by chi-squared test, exact probability test, t-test, one-way ANOVA, two-way ANOVA, Mann-Whitney-U test or Kruskall-Wallis test for univariable analysis. The multiple regression was used in the multivariable analysis to adjust for extraneous variables. 	Results: The total expenditure of treatment associated with chronic obstructive pulmonary disease were estimated to be 7,656.72 Baht per year per patient. There were no trends of change according to age, duration of illness, or disease severity. After adjusting for gender, age, education, occupation and income differences, patients with chronic obstructive pulmonary disease were paying 7,520.65 Baht per year more than the comparison subjects, or 431 times as much. The costs were estimated to be 4,114 million Baht per year for the patients all over the country. When added to 8,297 million Baht per year paid by the civil sectors, the total costs were 12,411 million Baht per year, which approximated 0.27% of the gross national product, or 4.40% of the national expenditure on health in 1998. The quality of life among patients with chronic obstructive pulmonary diease scored fair, and was poorer than that of the comparison subjects in every way, except for the environmental domain. The quality of life worsened according to the disease severity, but was unchanged according to age and the duration of illness. Patients who became ill at the age of below 50 years were estimated to loss 11.07 years of quality adjusted life throughout their illness. The total expenditure of treatment associated with coronary heart disease were estimated to be 17,746.44 Baht per year per patient. There were trends of decreasing according to age and the duration of illness, but increasing according to the disease severity, and in patients classified as having a heart failure. After adjusting for gender, age, education, occupation and income differences, patients with chronic obstructive pulmonary disease were paying 14,767.06 Baht per year more than the comparison subjects, or 164 times as much. The costs were estimated to be 840 million Baht per year for the patients all over the country. When added to 14,060 million Baht per year paid by the civil sectors, the total costs were 14,900 million Baht per year, which approximated 0.32% of the gross national product, or 5.28% of the national expenditure on health in 1998. The quality of life among patients with coronary heart disease scored good and fair, and was poorer than that of the comparison subjects in every way, except for the environmental domain, in particular items related to income adequacy, extense of information and health service received, and travel convenience. The quality of life worsened according to the disease severity, but improved according to age, and was unchanged according to the duration of illness. Patients who became ill at the age of below 50 years were estimated to loss 9.19 years of quality adjusted life throughout their illness. 	Discussion: The direct medical costs of treatment were the major component of the total expenditure. Decreasing the cost of medical service should therefore, lessen the economic burden of these patients. Some of the expense were used for travelling in the seek of treatment in distant localities. Increasing the diagnostic and treatment capacity of the local hospitals to meet with the standard and with the patients’ acceptance should reduce this portion of expense, through the decrease in the number of patients seeking health care in hospitals located in large cities, including Bangkok. The direct non medical costs mostly comprised of travelling and food expenditure and the lost of income of persons accompanying the patients. By referring patients back to their local hospitals, these cost should be reducible. The patient’s quality of life worsened according to the disease severity. Rehabilitation programme which has an impact on the patients’ cardiac, pulmonary and vascular function, and which is manageable at domestic level, should be considered in order to decelerate the above mentioned worsening quality of life.