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April 2012
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Substance use continues to be recognized as one of the major health and social issues in the Caribbean. The use of alcohol and illicit drugs is known to significantly affect health in the context of morbidity and mortality, but this has never been quantified in Trinidad and Tobago. Substance use affects mortality, either through toxic effects on the body’s metabolism or through the elevation of risk for a variety of medical disorders for which the user becomes predisposed. Substance use can contribute to poor judgment and impaired decision-making, resulting in high-risk behaviour that further increases the risk of morbidity and mortality from accidents or acts of violence. The relationship between substance use and mortality is very important in the context of planning and implementing drug prevention policies. Mortality is the final common pathway of all life, and behaviour is powerfully influenced by fears related to the inevitability of death. There is growing concern that mortality related to substance use is increasing worldwide, particularly in the industrialized world. From an 18-year follow-up study in Italy, the mortality risk for men and women dependent on substances is estimated to be 15 and 38 times (respectively) that of the general population. The other important consideration is that drug use, apart from overdose and poisoning, is never a direct cause of mortality. It contributes to the development of the pathology and/or the sequence of events that ultimately result in death but it is rarely the actual cause of death. Definition of a drug-related death is sometimes difficult and requires accurate historical and laboratory support to confirm its contribution to mortality. This, in turn requires sensitivity to the issue among doctors, especially pathologists, and the careful assimilation of information to establish the actual determinants. Support, in terms of resources to identify these links and encouraging families and friends to share information must also be part of the documentation process. Alcohol
In Trinidad and Tobago, most estimates of lifetime prevalence of alcohol use suggest rates in the range of 75-85% with first exposure likely to be in the peripubertal age range. This suggests that lifetime exposure to alcohol use is extremely lengthy for those who continue to drink throughout their lifetime. There is some indication that alcohol use is more common among Indo-Trinidadians and marijuana and other illicit drug use more common among Afro-Trinidadians, a pattern evident from as early as adolescence (Singh et al, 1991). Alcohol consumption has also been shown to be associated with the geographic prevalence of completed suicide in Trinidad. Tobacco
People who smoke are at greater risk of developing strokes, which are associated with increased mortality. Other diseases that contribute to smoking-related mortality are peptic ulcer disease and thyroid disease, though smoking may not be the only risk factor implicated here. Given the high rate of cardiovascular and cancer related deaths in Trinidad and Tobago, tobacco smoking has to be considered a significant risk factor in any cause related mortality analysis. Surprisingly little empirical information has been documented about the relationship between tobacco smoking and mortality in Trinidad and Tobago. Cocaine and Cannabis
The use of all psychoactive drugs increases the risk of accidents and road traffic accidents in particular with a corresponding impact on mortality. Habitual marijuana use, while not a significant contributor to mortality on its own, is associated with an increased risk of lung disease and injury implicated in mortality due to road traffic accidents and may also increase the risk of suicide in adolescents although it is unclear whether the disturbance in mood would have predisposed to the smoking of marijuana as a form of self medication. Little research to date has established the degree to which other drugs such as ecstasy, amphetamines and heroin are being used and affecting the population in Trinidad and Tobago, however it is clear that they are present and may present a growing threat in years to come. In a report about substance use related mortality prepared for the National Alcohol and Drug Abuse Prevention Programme (NADAPP), 19% of deaths occurring in Trinidad and Tobago over a three-year period (2003-2005) were directly related to substance use. Males were three times more likely than females to be so affected and in the 35-44 age group, they were ten times more likely than females to die from substance related causes. In the younger population (under 44 years) the main causes were unintentional injuries (road traffic and other accidents, homicide, suicide, drowning) which represented 64% of this population and HIV/AIDS and other infectious illnesses. In the older population, the main causes were cancer and heart and brain vascular disease, for instance, heart attacks and strokes. Alcohol use contributed to liver disease, gastrointestinal disease and unintentional injuries particularly among the older (over 44 years) age groups while cocaine and cannabis were more prevalent among the younger age groups. With regard to ethnicity, alcohol accounted for a greater percentage of deaths in Africans over 44 years and in East Indians who were less than 44 years, though overall, more East Indians (57%) were found to have alcohol related mortality. Alcohol related deaths were more common in the South Central area (61.3%) compared to the North East and Tobago. African ethnicity was associated with greater deaths for the other categories of drug use (62%). However this must be interpreted cautiously as deaths are recorded and registered where they occur and may not correlate with where people live. In general, substance use accounted for the greatest percentage of deaths in the mortality of the 35-44 age group and this was so mostly because this age group combined mortality from heart disease and unintentional injuries, including suicide and homicide. The health risks of alcohol have been previously described to account for more than 50% of medical admissions to the Port of Spain General Hospital (Prasad, 1979) and this is borne out here with the marked and significant preponderance of alcohol related deaths when compared with the other drugs and indeed with other causes of death. Some of the drug use, particularly in the case of unintentional injuries and road traffic accidents, was contextual and may not indicate long term substance dependence Alcohol use was common to all age groups, including the youngest age groups although deaths were predominantly seen in the over 44 age group. Preventive measures against the use of alcohol must include information related to the risk of mortality for both acute and chronic use. The impact of alcohol on judgment and impulsive behaviour needs to be measured more specifically in the younger age groups, particularly with regard to self harm and violent behaviour. Substance use related mortality is a more significant problem for males than females and this is consistent with reports on general use. This is especially so for long term alcohol use and is consistent with reports from the international literature. This is a factor therefore that contributes to earlier mortality in men and may be partly responsible for the lower life expectancy of men compared with women. This disparity applied across causes of death and was seen for the range of drugs as well as the range of causes. There is also the interesting finding that alcohol related mortality was approximately equally seen in both Africans and East Indians although epidemiological surveys suggest that alcohol use is more common in East Indians compared with Africans. It may be that some of the deaths due to vascular disease may have arisen from alcohol and cigarette use and therefore the impact on the East Indian population may have been more indirect. Future research needs to target specific drugs and employ a means of ready verification of drug use. Another interesting association was the relationship between deaths from HIV/AIDS and other infectious illnesses and substance use. Substance use increases risky sexual behaviour and predisposes them to contracting sexually transmitted diseases but it appears that it also further compromises the immune system and makes them more likely to suffer fatal consequences of these infectious diseases. It is also known that chronic alcohol use depletes the immune system but not much is known about the impact of cocaine and cannabis in this context. What can be gleaned is that high rates of cardiovascular related mortality are at least partly due to substance use and that deaths from unintentional injury and infectious illness are also related significantly to substance use. Additionally, alcohol remains the greatest single substance of abuse that affects mortality. Preventive measures must include information that alerts particularly young males that abuse of substances will shorten their life spans. This is the fourth in a series on mental health issues by Professor of Psychiatry, Gerard Hutchinson. Professor Hutchinson is the head of Department, Clinical Medical Sciences, School of Medicine, Faculty of Medical Sciences, EWMSC, UWI. Next: Depression |
Most of the work on drug use and mortality has been focused on alcohol, where deaths related to unintentional injuries and violence, suicide, road traffic accidents, malignant neoplasms and a range of gastrointestinal diseases rank highest. In the case of cardiovascular (heart) disease, alcohol in moderate amounts is proposed to have a protective effect but in excessive quantities can contribute to uncontrolled hypertension and strokes. In Canada, it is estimated that alcohol contributes to 6% of all deaths, which is consistent with findings from New Zealand which suggest a range of 3-9%. There is also age group delineation as in East Germany for example, 30% of deaths in the 25-44 age group are attributable to alcohol use (Britton et al, 2003). The mortality risks related to alcohol occur in women at lower levels of consumption. Alcohol related mortality is especially significant in the younger age groups where deaths due to accidents are more likely to occur than deaths from chronic disease. In addition, there is a strong relationship between population alcohol consumption and mortality from homicide, suicide and accidents. 
Nicotine or tobacco use has also long been associated with lung cancer specifically, and a greater risk for several other malignancies in the oral and pharyngeal areas. Smoking also contributes to increasing the risk for vascular disease and this must also be taken into account in any assessment of substance-related mortality. In the USA, it is estimated that cigarette smoking reduces life expectancy by 15-25 years and is the single most preventable cause of mortality. The danger of second-hand smoke is now acknowledged. Cigarette smoking, although not the only risk factor, is estimated to contribute to 20% of all deaths by heart attacks and about 30% of all cancer deaths. These cancers include lung cancer where smoking may account for up to 85% of deaths and cancers of the throat, mouth and oesophagus (Winkler et al, 2006). There are also higher rates of leukaemia and cancers of the kidney, stomach, bladder and pancreas among smokers. Interestingly, lung cancer patients who survive and continue to smoke face a greater risk of developing a second tobacco related cancer within ten years. 
Cocaine and other stimulant drug use are associated with cardiomyopathy (heart muscle disease), particularly after long term use. This may cause sudden cardiac death as there is the risk of raised blood pressure and increased pulse rate which may result in an increased risk of myocardial (heart) events. This risk is significantly increased when there is use of cannabis and alcohol as in the poly drug user/abuser. The range of other CNS stimulants including amphetamines and ecstasy are also implicated in this risk for cardiac death.