INTRODUCTION
The world drug report (2019) estimated the number of opioid users to be nearly 53 million worldwide, i.e., an increase of almost 56% from previous estimates. The higher estimates have been proposed to be the result of improved knowledge of the extent of drug use.[ 1 ] In India, the prevalence of opioid use is 2.06% among adult males, and heroin is the most common opioid used (1.14%).[ 2 ]
The impact of opioid use on various domains of the life (viz., social, occupational, financial, sexual, legal, etc.) of an individual has been highlighted in the literature. Prolonged opioid use has been shown to produce sexual dysfunctions. These dysfunctions may even worsen during the initial phase of abstinence.[ 3 ] Sexual dysfunctions are one of the most common reasons for relapse into opioids, despite also being a consequence of prolonged opioid use.[ 4–7 ] Yet they are less explored during clinical interviews probably due to privacy concerns and hesitation on the part of clinicians or patients or both. The prevalence of sexual dysfunction varies from approximately 30% to more than 90% in some studies, depending upon the selection criteria, study population, type of scales, type of opioid used, and type of methodologies employed.[ 5 , 8–11 ] Most of the conducted studies have not incorporated a control group in their methodology. Other limitations include not using standardized instruments, focusing on only one sexual dysfunction , smaller sample sizes, and a heterogenous population, leading to variable findings across studies.
Few studies have also highlighted that sexual dysfunction may affect the social and emotional well-being of individuals as well as their marital relationships, eventually affecting the outcome of treatment.[ 6 , 7 , 12–14 ] A study done from our center assessed the sexual dysfunction , satisfaction, relationship with their sexual partners, and sexual quality of life among sexually active, married, treatment-naive male patients with heroin dependence and found that they performed poorly on all domains.[ 15 ] Apart from the above-mentioned studies, emotional aspects associated with sexual functioning are rarely discussed and none are available comparing patients who are treatment-naïve with those who are treated.
A concomitant problem associated with sexual dysfunction and substance is sexual behavior. High-risk sexual behavior has been defined in the context of substance use in various ways ranging from promiscuity and having multiple sexual partners to practicing unnatural/unprotected sexual intercourse, or intercourse under the influence of a substance.[ 16 ] Most of the Indian literature on the practice of risky sex amongst opioid users is restricted to people who inject drugs (PWIDs).[ 17–22 ] Other limitations include heterogeneous samples, small sample sizes, and not using standardized instruments. We researched to comprehensively assess the sexual experiences, perceived effects of substance, knowledge, and practice of risky sex amongst individuals of heroin dependence and found that such individuals had poor knowledge and high frequency of risky sexual behaviors.[ 23 ]
To summarize, while there is extant literature on the association between opioid use and sexual dysfunction and risky sexual practices, studies comparing treatment-naïve active users of illicit opioid (heroin) with those individuals under regular treatment (buprenorphine-maintained) on these aspects is limited. Moreover, very few studies have assessed the emotional aspects of sex. It is important to understand these aspects of sexual functioning in opioid users as well and compare them with those who are seeking treatment. The effect of treatment on these aspects of sexual functioning remains equivocal.[ 24–27 ] They have been known to be intricately linked to the initiation, continuation, and relapse of opioids. We thus aimed to assess the sexual behavior, functioning, satisfaction, quality of life, and sexual relationship amongst sexually active married males on buprenorphine maintenance treatment and compare it to those individuals with heroin dependence who were treatment naïve.
METHODS
Study type and settings
A cross-sectional study was taken up in the outpatient department of a tertiary care addiction treatment facility, affiliated with a medical school. The National Drug Dependence Treatment Center (NDDTC) comprises general and specialty outpatient, inpatient, and community clinics to provide care to the clientele, which majorly comprises patients with opioid dependence. Treatment of opioid dependence at the center generally utilizes a detoxification approach (with the initiation of naltrexone subsequently) or supervised opioid substitution treatment in the form of buprenorphine.
Study participants
Study participants were recruited by purposive sampling. Married adult males with a diagnosis of opioid dependence syndrome, as per the international classification of diseases-tenth edition (ICD-10) were recruited if they were currently (last one month) sexually active (involved in any kind of sexual intercourse, viz., vaginal/anal/oral) and living with their partner. Only those patients who were using heroin as the predominant substance of use were included in the study. They were recruited if they were treatment-naïve, i.e., seeking formal treatment for addiction for the first time (Group I) or under treatment from the center and abstinent (as per self-report) from heroin with buprenorphine maintenance treatment for at least the past 3 months (Group II). Those who had ever injected drugs in their lifetime were categorized as people who inject drugs (PWID). Those with a history of dependence on any other psychoactive substance as per ICD-10 (except tobacco), significant psychiatric/cognitive/medical comorbidity (as per history and clinical examination), or those unwilling to participate were excluded from the study.
Study instruments
The study instruments included semi-structured proforma comprising sociodemographic and clinical details. In addition, details on sexual history, particularly focusing on various aspects of high-risk sexual behavior ,[ 16 ] were assessed. For example, age at the first sexual encounter, number of sexual partners in a lifetime, use of condoms, premarital sexual intercourse, intercourse with commercial sex workers/casual partners, symptoms suggestive of sexual diseases, etc.
Scale for assessment of sexual dysfunction : Scales for sexual dysfunction were applied which included an index for premature ejaculation (IPE) and an index for erectile function (IIEF).[ 28 , 29 ] Erectile dysfunction, on IIEF, is defined by a score less than 25 on the erectile function domain of IIEF. Premature ejaculation, on the other hand, is not defined within the scale but has been defined in certain studies as a score less than 50% of the total score on IPE.[ 30 , 31 ] Apart from erectile dysfunction and premature ejaculation, other sexual dysfunctions were not assessed in our study. We chose to assess only these two sexual dysfunctions as they are commonly encountered in our clinical population and are easily assessed using structured scales.
Scales for assessment of the sexual relationship, satisfaction, and sexual quality of life : For assessment of sexual relationships , satisfaction, and sexual quality of life , three scales, viz, the Self-esteem and Relationship Questionnaire (SEAR),[ 32 ] the New Sexual Satisfaction Scale-Short form (NSSS-S),[ 33 ] the Sexual Quality of Life Questionnaire-Male (SQoL-M),[ 34 ] were used.
SEAR : It is a 14-item scale that assesses self-esteem and relationship through Likert scoring.[ 32 ] A cutoff of 50% has been used in some studies.[ 31 ] Internal consistencies of all domains are more than 0.8.NSSS-S : It is a Likert-type scale assessing satisfaction associated with the sexual activities of the partner and self. It has two subscales: ego-centered subscale (10 items) and activity/partner-centered subscale (10 items).[ 33 ] The internal consistency and test-retest reliability of the scale is good (>0.9).SQoL-M : It is an 11-item Likert-type scale, assessing an individual’s perception of his sexual quality of life .[ 34 ] The internal consistency and test-retest reliability of the scale is >0.7. All scales were translated into Hindi as per WHO translation-back translation method (except IIEF and IPE which were already available in Hindi).
Procedure
Ethical clearance was taken from the institutional ethical committee before initiating the study. After screening the patients for the eligibility criteria, the patients were recruited after taking informed consent. It was ensured that the patients are not in active withdrawal during clinical assessment by clinical examination. After assessing socio-demographic, clinical, and sexual history, structured scales (IIEF, IPE, SEAR, NSSS-S, SQoL-M) were applied. All assessments were carried out in a single session lasting around 1–1.5 hours. Data were collected from October 2018 to February 2021.
Statistical analysis
Statistical analysis was carried out using SPSS 20.0. Descriptive data were described using means, standard deviations, frequencies, and percentages. Comparison between two groups (treatment naïve patients and patients on buprenorphine) were carried out using independent sample t-test (continuous variables) and Chi-square or Fischer’s exact test (categorical variables).
RESULTS
A total of 112 individuals (Group I: 63; Group II: 49) were recruited in the study. The socio-demographic details of the two groups have been shown in Table 1 . The mean age of the individuals in the treatment-naïve group, i.e., group I (approximately 32 years) was significantly lower than those under opioid substitution treatment, i.e., group II (approximately 37 years). All were males, married, and cohabiting with their partners. While the education levels were not significantly different, a higher proportion of individuals were employed in group II (94% vs 70%). On the contrary to higher employment in group II, the mean total family income was relatively higher in group I (29,365 INR vs 17,163 INR).
Table 1: Sociodemographic characteristics of individuals in group I and II (n =112)
Table 2 presents the clinical details of patients in both groups. The age of onset was comparable in both groups, but the duration of tobacco use was higher in group II (possibly owing to the higher average age in group II). Similarly, the duration of heroin use was also higher in group II (11 vs 8 years). While the frequency of individuals using alcohol was comparable in the two groups, cannabis use was found to be more frequent in current users (70% vs 41%). Heroin users were spending 1,382.5 ± 1259.4 INR daily on average on heroin. Individuals in group 2 were on treatment for around 36.8 ± 27.3 months on average with the mean daily dose of buprenorphine being 12.29 ± 3.83 mg. No differences were seen in injecting behavior between the two groups.
Table 2: Clinical characteristics of individuals in group I and II (n =112)
The characteristics of sexual history and behavior have been described in Tables 3 and 4 . No differences were seen in the average number of sexual partners in a lifetime, age at the first sexual encounter, condom use, or lifetime history of casual partner sex/sex with commercial sex workers/sexual intercourse under intoxication/intercourse with males/practicing anal sex/premarital sexual intercourse. However, differences were seen in the current practice in the following characteristics: casual partner sex, sex with commercial sex workers, and sex under intoxication. The practice of oral sexual intercourse was higher in group I (both lifetime and current) as compared to group II. A sizeable, but comparable, number of individuals had experienced symptoms of sexual disease, like burning micturition, urethral discharge, genital lesions, ulcers, or pain (35% and 26%, respectively), and had coerced sex on someone during their lifetime (17% and 10%, respectively). The number of individuals who had undergone HIV testing was higher in group II.
Table 3: Comparison sexual history between individuals in group I and II (n =112)
Table 4: Comparison sexual behavior between individuals in group I and II (n =112) Lifetime vs Last Month
Table 5 and Figure 1 present mean scores on various scales to measure, sexual functioning, sexual satisfaction , quality of life, and sexual relationship with the partner. Group II had significantly higher scores on all the scales as compared to group I, indicating better sexual functioning, sexual satisfaction , quality of life, and sexual relationship with the partner. The frequency of individuals experiencing erectile dysfunction in the erectile functioning domain of IIEF was 49 (~78%) and 19 (~39%) in groups I and II (χ2 = 17.578; P < 0.001), respectively. Frequency of premature ejaculation, defined by a score less than 50% in total IPE scores, was present in 19 (~30%) and 3 (~6%) individuals in groups I and II, (χ2 = 10.088; P = 0.001), respectively.
Table 5: Comparison sexual scales between individuals in group I and II (n =112)
Figure 1: Comparison sexual scales between individuals in group I and II. International Index of Erectile Function (higher scores indicate better functioning); Index of Premature Ejaculation (higher scores indicate better functioning); New Sexual Satisfaction Scale (higher scores indicate better satisfaction); Self-esteem and Relationship Questionnaire (higher scores indicate better self-esteem and relationship); Sexual Quality of Life Questionnaire (higher scores indicate better quality); *p < 0.01
DISCUSSION
The study compared sexual behavior, dysfunction, as well as the sexual quality of life and relationship among treatment-naïve patients and those who were on long-term treatment with buprenorphine. To the best of our knowledge, this is the first study to demonstrate this comparison. We found that many aspects of high-risk sexual behavior , as defined in the literature,[ 16 ] were comparable between the two groups during their lifetime. However, their current practices differed from the treatment-naïve population indulged in significantly more frequency of risky sex than those who were taking regular treatment. This could either be because of lower indulgence in all types of risky behaviors the following engagement into treatment or cohort effect, due to differences in the age between the two groups.
The two groups differed in age as expected since the former was only recently seeking treatment while the latter was in treatment for nearly three years on average. The same difference was also extrapolated in the difference in duration of tobacco and heroin use between the two groups. Concerning monthly family income, those who were current users had higher family income, albeit a lower percentage being employed currently. While higher rates of unemployment amongst active users of heroin is an expected finding,[ 35 ] the overall family income of active users was higher. Long-term unemployment has been shown to increase the consumption of substance use.[ 36 ] It has also been seen that more lost money lying around and being unemployed (providing them more time on hand and less to lose from drug consumption) may increase the consumption of the substance.[ 35 ] Economic theory also suggests that economic slowdowns are associated with a reduction in substance use and a rise in personal income may increase the frequency of use of the preferred substance.[ 35 ] Cannabis use was also found to be higher amongst active users than those who had stopped using illicit opioids while alcohol use was comparable. This could probably be explained by the fact that cannabis use may concurrently be reduced with a reduction in the primary illicit substance (i.e., heroin) while alcohol being a licit drug continued an occasional basis. It could also be a confounding factor associated with higher sexual dysfunction in group I, as has been highlighted in previous literature.[ 37 ] The average dose of buprenorphine was nearly 12 mg per day, which is higher than what was previously seen in other Indian studies.[ 38 , 39 ] However, another Indian study has shown that higher doses of buprenorphine maintenance (up to 10 mg) may be associated with lesser drug liking/craving.[ 40 ] So, in our population, relatively higher doses of buprenorphine may have been instituted to ensure reduced craving or euphoria of the illicit drug over the long term thus leading to better retention into treatment.
All aspects of sexual functioning and relationships were poorer in active users than in those who were on buprenorphine maintenance treatment. Before this study, we carried out the study in treatment-naïve individuals using heroin in dependent pattern, which was one of the first studies assessing the emotional aspects of sexual functioning.[ 15 ] SEAR was used for the first time in such a population to assess sexual relationship quality. Prior studies have shown strong correlations between different domains of IIEF and IPE and SEAR domains.[ 31 ] This study is an extrapolation of our previous study in comparing treatment-naïve individuals with those on treatment for a prolonged period. In addition to our previous study, very few studies have assessed patients with opioid dependence with a stable sexual partner.[ 41 , 42 ] Koolaee et al (2015)[ 41 ] only assessed sexual satisfaction amongst opium and methamphetamine users, while Sethi et al .[ 42 ] studied only erectile functioning in an opioid-dependent population.
Both erectile dysfunction and premature ejaculation were found to be higher in active users as compared to buprenorphine-maintained abstinent patients (78% vs 39% erectile dysfunction; and 30% vs 6% premature ejaculation). The prevalence of both these entities is highly variable in different studies.[ 3 , 8 , 24 , 43–46 ] The difference is attributable to the type of selection criteria employed, the type of scale used, the duration for which the dysfunction is assessed (last one month vs lifetime), and the characteristics of the study population. Moreover, we did not enquire about premorbid sexual functioning in our study population. While sexual dysfunction was higher in untreated individuals, as compared to the general population,[ 47–49 ] the prevalence of sexual dysfunction , particularly erectile dysfunction, was higher in both groups. The prevalence of premature ejaculation in the second group (buprenorphine-maintained) was, however, comparable to the general population. This could also be attributable to either difference highlighted above or near complete resolution of the problem of quitting the substance. Albeit literature suggests that advancing age is often associated with most sexual problems,[ 49 , 50 ] the treated group despite being significantly older than the active users had lesser sexual problems on all structured scales, making the findings of our study even more important in explaining the effect of heroin on sexual functioning.
Our study has added to the currently existing but equivocal evidence of treatment either worsening or improving sexual dysfunction .[ 24–27 ] Thus, this study holds various other clinical implications. Those who are taking regular treatment and involved in lesser substance-related behavior, are also indulging in relatively less risky sexual behavior. Since it was a cross-sectional study, the association may or may not necessarily be causal. However, considering that patients’ demographic and clinical profile was largely similar, the difference in sexual behavior and functioning is accounted for by being on maintenance treatment. Sexual dysfunctions and poor sexual relationships may be a cause and/or consequence of substance use. However, it may be worthwhile to focus on all types of risky behaviors (substance-related and sex-related) concurrently as a part of the comprehensive treatment strategy. Educating patients about the vicious cycle of using the substance to compensate for sexual dysfunction which in turn may cause/worsen sexual dysfunction and relationship is an important part of treatment. Clinicians must also understand to explore this very important yet ignored entity while assessing and managing the substance-related disorder.
To our knowledge, this is the first study to compare treatment-naïve and treated patients head-to-head for high-risk sexual behavior , sexual dysfunction , and various emotional aspects of sexual relationships . However, the findings should be understood in light of certain limitations. It was a cross-sectional study, with purposive sampling, thus causal attributions must not be drawn. The sample is taken from a tertiary care addiction treatment facility limits the generalizability of the findings. As we excluded those who were sexually inactive, severe dysfunctions would have been excluded. We did not assess other sexual dysfunction than erectile dysfunction and premature ejaculation. Since those who were taking the treatment had been abstinent for a significantly longer duration, there may be issues of recall bias for their substance-related behavior, and sexual life during that phase. In addition, the results may be confounded by psychosocial interventions in the buprenorphine-maintained patients, and other physical disorders in our study population, both of which have not been assessed in our study. We also did not assess sexual functioning before the onset of substance use. The scales translated into Hindi were not validated and power analysis was not carried out.
In the future, it may be worthwhile to study these individuals longitudinally (e.g., from being treatment naïve to prospectively becoming abstinent on treatment), comparing different kinds of treatment (buprenorphine vs methadone/agonist vs antagonist) as well as different substances (e.g., opioid vs alcohol, or different varieties of opioids), taking larger community samples. A head-to-head comparison with the general population is also important and should be studied. It would also be interesting to study the same parameters among female substance users.
CONCLUSION
Individuals with opioid use disorder who have never sought treatment tend to be engaged in more frequent high-risk sexual behavior as compared to those who have been maintained on buprenorphine treatment for about three years. Patients on buprenorphine treatment also report better sexual functioning, relationship satisfaction, and sexual quality of life . These aspects must be noted and utilized in educating patients seeking treatment for heroin dependence and comprehensive management of the individual for both substance-related problems and the sexual problem should be targeted in the treatment.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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