Clinical observations demonstrated that adverse effects of psychoactive substances were associated with the addiction period and route of administration. The psychoactive substance use more than 2 years causes more profound effects. Psychoactive substance users commonly have nutritional problems since they spend their money largely for drugs (
13). Coexistence of psychiatric disorders in drug addicts is also important since some psychiatric disorders may cause loss of appetite and poor nutritional status and changes in biochemical parameters (
14).
Clinical studies showed that long-term use of opium and heroin can affect serum glucose, potassium, calcium, uric acid and cholesterol levels (
12). In our study, we found a significant difference in GGT, uric acid, creatinine, urea, albumin, and AST medians between the dependent and control groups (P < 0.05).
Studies about the effects of opium addiction on blood glucose showed that the opium-dependence decreased fasting blood glucose temporarily without any effect on Hemoglobin A1c (
15). We found a statistically significant decrease in glucose levels only in patients tested positive for benzodiazepine (P < 0.05). Some psychoactive substances may affect gluconeogenesis so that blood glucose levels may decrease, especially in cases with poor nutrition.
Some people believe that psychoactive substances like opium can have beneficial effects on blood lipid profile and cardiovascular disease, but clinical observations demonstrated that opium can increase risk of atherosclerotic plaque formation and adversely affect lipid profile in animal models (
16). We found a statistically significant increase in triglyceride levels in ethylglucuronide group (P < 0.05). In our study, we did not found statistically significant difference in total cholesterol, low density lipoprotein (LDL), and high density lipoprotein (HDL) levels between dependent and control groups (P > 0.05). Cardiovascular side effects of some psychoactive substances may not be attributed to changes in lipid profile. There is a need to conduct a prospective study with the larger sample size for the prevalence of the cardiovascular disease.
Another study, which was performed on opium addicts showed that serum adiponectin levels were decreased but no significant change was observed in serum leptin levels. It was also indicated in previous studies that a decrease in adiponectin levels can be associated with an increased risk of metabolic disorders like insulin resistance and cardiovascular disease since it has known antidiabetic and antiatherogenic effects (
17).
Coexistance of several types of infections like hepatitis may affect nutritional status. Addicts usually prefer carbohydrates instead of animal proteins. Changes in nutritional patterns may also be related with changes in albumin levels in these patients (
18). We found a statistically significant difference in albumin levels between the drug-dependant and control groups. In our study, the amount of total protein showed a significant difference only in the benzodiazepine dependent group (P < 0.05). Since in our study, patients with significant derangements were referred to specialized medical centers for further assessment and excluded from the study, changes in their albumin levels may not be due to viral infections or metabolic disorders.
In a previous study, it has been demonstrated that morphine consumption for long period in animal models increases uric acid and creatinine levels (
19). We found a statistically significant decrease in uric acid and creatinine levels in the dependant group compared to the control group (P < 0.05). Poor living conditions and nutritional factors like low protein intake may likely to contribute to changes in biochemical parameters in psychoactive substance users.
Opioids have effects on kidney, central nervous system and other organs. These effects on renal system include changes in urinary output and urinary sodium excretion (
20). Divsalar et al. showed that a sodium level in the heroin-dependent group did not change; however, it was significantly high in the ex-heroin dependent group compared to the control group. However, no significance difference was found in potassium and calcium levels between the ex-heroin dependent and control groups (
14). We found that the concentration of sodium in the serum of the opium-dependent and benzodiazepine dependent groups was significantly increased compared to the control group (P < 0.05). No statistically significant difference was observed in calcium levels between the dependent and control groups (P > 0.05).
Routine biochemistry, and hematology parameters, and vitamin, and mineral levels are affected by nutritional factors. Nutritional status of addicted patients involved in treatment programs was changed after the treatment. Determining the differences in biochemical parameters, vitamin and mineral levels between addicts and healthy subjects may help to define individuals at nutritional risk and provide these patients with the corrective nutritional programs (
18).
In this study we tried to describe the extent of changes in various blood parameters due to psychoactive drug use. Previous literature has revealed effects of some psychoactive substances on serum biochemical parameters. Our study involves a range of psychoactive substances like heroin, cannabinoids, cocaine, benzodiazepine, opiate, buprenorphine, amphetamine, extacy, ethyl glucuronide and their potential effects on many biochemical parameters. Raising awareness about potential adverse effects of psychoactive substances may warn those using these substances for the first time. Health problems associated with physiological side effects of these substances may increase economic burden on health care resources. Therefore, in psychoactive substance users defining the real need for intensive monitoring and treatment programs are extremely important.