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 Table of Contents  
REVIEW ARTICLE
Year : 2021  |  Volume : 8  |  Issue : 2  |  Page : 70-76

Validated scales for substance use disorders in the geriatric population: A scoping review


1 Additional Professor, NDDTC, All India Institute of Medical Sciences (AIIMS), New Delhi, India
2 Scientist B (Medical), ICMR Project, NDDTC, All India Institute of Medical Sciences (AIIMS), New Delhi, India
3 Associate Professor, NDDTC, All India Institute of Medical Sciences (AIIMS), New Delhi, India

Date of Submission24-Sep-2021
Date of Decision05-Nov-2021
Date of Acceptance11-Nov-2021
Date of Web Publication31-Jan-2022

Correspondence Address:
Dr. Roshan Bhad
MD DNB, R No 4096, Department of Psychiatry, AIIMS, New Delhi - 110 029
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jgmh.jgmh_38_21

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  Abstract 


Substance use disorders in the elderly population can be assessed through scales and questionnaires. These scales are used for not only screening for substance use disorders but also for assessment for improvement with time and/or intervention. Validity parameters of these scales help us know how do they perform during application in the clinical or community setting. The objective of the review was to (1) review available validated screening tools for substance use disorders, (2) summarize elderly-focused studies, and (3) provide recommendations for use in clinical care. We aimed to review the validated scales of substance use disorders in the geriatric population. We looked at PubMed and Web of Science databases for identifying English language peer-reviewed publications that reported at least one validity parameter for scale in geriatric patients with substance use disorders. We identified 22 studies, with majority of them focusing on alcohol use disorder. Alcohol Use Disorder Identification Test and Cut Down, Annoyed, Guilty, and Eye-Opener Questionnaire (CAGE) were the most common scales used in the population. While most of the studies reported acceptable area under receiver operator curve, sensitivity, and specificity, some of the studies reported lower sensitivity/specificity at optimal cutoff. Validity parameters of various scales have been assessed in the geriatric population. Using suitable cutoffs, they can be useful in the screening of elderly individuals with substance-related problems, so that due evaluation and care can be provided. More instruments need to be assessed for validity to diagnose tobacco use disorders, benzodiazepine use disorders, and other substance use disorders.

Keywords: Addiction, assessment, Alcohol Use Disorder Identification Test, geriatric population, scales, screening, substance use disorders


How to cite this article:
Sarkar S, Sood E, Bhad R, Mishra A. Validated scales for substance use disorders in the geriatric population: A scoping review. J Geriatr Ment Health 2021;8:70-6

How to cite this URL:
Sarkar S, Sood E, Bhad R, Mishra A. Validated scales for substance use disorders in the geriatric population: A scoping review. J Geriatr Ment Health [serial online] 2021 [cited 2022 May 24];8:70-6. Available from: https://www.jgmh.org/text.asp?2021/8/2/70/336910




  Introduction Top


Substance use disorders have been associated with several health problems among users.[1],[2],[3] Tobacco, alcohol, and drug use disorders are associated with ailments of the respiratory system, cardiovascular system, gastrointestinal system, endocrinological system, and others. Substance use disorders cause not only health problems but also are associated with psychosocial and economic adverse consequences such as familial strife, increase in criminality, lost productivity, and loss of personal income.[4],[5] Substance use disorders can be addressed by several approaches including pharmacological, psychotherapeutic, rehabilitation, self-help groups, and others. Effective treatment options are available for several substance use disorders, and patients undergoing treatment have reported cessation or reduction of substance use with treatment, and improvements in physical health, quality of life, and familial functioning.[6],[7]

In the treatment process assessment of the substance use disorder forms, the first step is ascertaining whether a substance use disorder is present and to evaluate the severity of the problems. The data collection instruments, such as scales, questionnaires, and instruments which are developed for its usage in specific populations and conditions, help in the process of assessment for substance use disorders.[8],[9],[10] Scales provide an objective measure to assess the cross-sectional condition of the individual, and repeated administration can provide a longitudinal course of the health state of the individual. Scales have been developed for alcohol, tobacco, opioids, and other substance use disorders, and some of these cater to more than one substance of use. Scales are available for different aspects of substance use disorders such as screening, assessing severity, risk category, motivational stage, quality of life, treatment preferences, treatment outcome, and other facets. Some of the scales and instruments have also focused on substance use among specific populations such as children, adolescents, pregnant women, and the elderly.

Geriatric population is gradually increasing the world over. As per the United Nations estimate of macrotrends, the current life expectancy for India is 69.96 years, with an increase of 0.33% relative to the year 2020. As longevity improves, the proportion of the population classified as old and oldest old is showing steady increases. Substantial evidence suggests that substance use problem in the geriatric population is underestimated.[11] Many of the substance use disorders, which are commonly found in the younger population, are being increasingly seen in the elderly population as well.[12],[13] This suggests that clinical encounters with elderly patients with substance use disorders are likely to increase in future. The presence of substance use disorders in the geriatric population has adverse consequences on health, and may lead to genesis or exacerbation of the health problems.[12],[14] Due to cognitive decline, sensory impairment in older age use of self-rated scales may be a challenging task. Thus, assessing the presence of substance use problems accurately is important to cater to their needs. Some of the scales have been used to determine substance-related problems in the elderly population. Validation parameters of such scales help to assess how the scale performs in the clinical or community setting. An understanding of the validation parameters can help us to understand whether a scale is being able to measure appropriately what it is supposed to measure. In this scoping review, we aimed to assess the validity parameters of the scales that have been used for substance use disorders in the elderly population.


  Methods Top


The review aimed to summarize the scales that have been validated for elderly individuals with substance use disorders. We searched PubMed and Web of Science databases for identification of peer-reviewed full-length original research. Those articles which reported at least one validity parameter, for example, internal consistency, sensitivity, specificity, concurrent validity, divergent validity, reliability, were included. Those articles which did not report any of the validity parameters separately for the elderly if multiple population groups had been included and articles in non-English language were excluded. The searches were done in July 2021 by one of the authors.

Study selection

Population

We did not use a defined age group; all studies with the elderly, aged, or geriatric population as defined by the authors were included.

Content

All studies which included the selected population, scales for substance use, and validity parameters were included.

Context

Selected studies were English-language publications, where full text was available.

Exclusion criteria

Studies which did not report any of the validity parameters for scales for substance use in the geriatric population or validity parameters separately for the elderly if multiple population groups had been included and studies in non-English language were excluded.

The search string for making the searches was “(“Elderly” OR “Old” OR “geriatric”) AND (scale OR instrument OR questionnaire) AND (valid OR reliability) AND (alcohol OR tobacco OR cigarette OR opioid OR heroin OR opiate OR cannabis OR marijuana OR substance OR “illicit drug” OR cocaine OR methamphetamine OR solvents) AND (abuse OR dependence OR disorder OR “harmful use”).” We looked at cross-references of the included studies for identification of further studies. Hand searches of libraries and contacting of the experts were not conducted as a part of the review.

All relevant abstracts were reviewed independently by the investigators (RB and SS). We extracted the relevant data of the study details, country of origin of the study, the scale assessed, the definition of the geriatric population, details of sample size and demographic parameters, the validity parameters studied, and the findings of the validity parameters. Data extraction and synthesis were done by two of the investigators (SS and ES). Qualitative inferences were drawn from the included studies, and quantitative synthesis was not done.


  Results Top


Of the 516 records identified in the search, 22 studies fulfilling the inclusion criteria were included in this scoping review. We enumerate 22 studies looking at the validity parameters of various instruments in the elderly in [Table 1].
Table 1: Included studies of validity of scales for substance use disorders in the elderly population

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The age of the elderly in these studies was more than 60 years and above, except one study by Johnson-Greene et al., 2009,[25] where age was more than 50. The sample sizes of these studies have ranged from 22 to 1068. Some of the studies have looked at the community samples, while others have looked at the elderly in the hospital setting. Few studies were based on only male participants,[16],[18],[28],[29] and others comprised a mixed population. The specific exclusion of patients with cognitive impairment or possible dementia as per screening tests, such as Mini–Mental State Examination (MMSE), was also mentioned by some studies. While most of the studies looked at patients with alcohol use disorders, some of the studies looked at the elderly with other substance use disorders.[17],[19],[23] Studies originated from the USA, Austria, Brazil, Canada, Germany, Korea, Norway, Singapore, Spain, Sweden, Switzerland, and the UK.

Among the scales or questionnaires, Alcohol Use Disorders Identification Test (AUDIT) and Cut Down, Annoyed, Guilty, and Eye-Opener Questionnaire (CAGE) were the most common ones. Apart from these, the Michigan Alcohol Screening Test and its geriatric version, Alcohol-Related Problems Survey, Severity of Dependence Scale, and Alcohol, Smoking and Substance Involvement Screening Test were used. The validity parameters reported commonly were Area Under the Receiver Operating Characteristics (AUROC), sensitivity, specificity, Cronbach's α, discriminant validity, concurrent validity, and factor analysis. One of the studies reported exploratory factor analysis, Mokken scaling analysis, and Rasch analysis.[20] The studies reported fairly good AUROC with the scales, except for one study which reported AUROC of 0.56 for AUDIT.[28] Low sensitivities for cutoff scores of AUDIT were reported by two studies, but other studies reported good sensitivity and specificity with AUDIT.[27],[28] AUDIT-C had better sensitivity and specificity compared to AUDIT. CAGE also had better sensitivity and specificity across different studies. It can be argued that shorter scales have better clinical utility in this population.

We excluded the following screened studies: Chaikelson et al., 1994[37] (looked at lifetime alcohol use but not alcohol use disorder); Lintzeris et al., 2016[38] (did not report any validity parameter of substance use disorder); and Clay, 1997[39] (did not report any validity parameter of substance use disorder).


  Discussion Top


Several studies have looked at establishing the validity of screening tests for detecting substance use disorders in the elderly population. Most of the studies that we could identify focused on alcohol use disorders. Less were available on other substances of use (including tobacco use disorders). Possibly, this is based on clinical observation that many elderly individuals continue to use alcohol, but there is a difficulty in discerning whether the alcohol use is frequent and problematic. Many neurological and cardiovascular adverse outcomes can be attributed to heavy alcohol use,[40],[41],[42] and there lies the utility of finding out whether there exists an alcohol use disorder in the elderly population. Among the other substances (apart from tobacco), benzodiazepines are common medications of abuse among the elderly population and screening instruments have assessed this class of medications.

Many of the scales or questionnaires used in the elderly population have been developed for the adult population. Varied cutoffs have been reported in the adult population, with each of the cutoffs having its own sensitivity and specificity parameter.[43],[44] Similar findings echo for the elderly population, with the optimum balance between sensitivity and specificity being achieved at various cutoff scores, that differ across the studies. The optimal cutoff scores depend on not only the prevalence of the condition of interest (substance use disorder) but also what threshold we would like to have for false positives or false negatives.

One of the pragmatic challenges is to use a self-rated scale in the elderly population. Impairment in reading or gradually occurring cognitive impairment may lead to difficulty in administration of self-rated screening instruments. While one approach is to exclude those who have cognitive impairment (as reflected by MMSE scores lesser than a given threshold), another approach is to read out the questions to the participants. It can be argued that elderly individuals with cognitive problems and difficulty in activities of daily living are less likely to systematically procure and consume substances.

The practical utility of the scales lies in them being used for the screening of substance use disorders in the clinical or the community setting. Hospital waiting rooms may be a suitable place where these self-assessment instruments are used to pick up individuals with substance-related problems. In addition, individuals hospitalized for medical issues can also be assessed during their recovery so that intervention can be provided when necessary. Screening, Brief Intervention, and Referral to Treatment[45],[46] is a simple approach that can help to decide what level of intervention is required and take further action appropriately.

One of the issues pertaining to the use of the scales is the need for adaptation or validation of the international context. For example, we could not find any validity study from India. The direct application of some of the scales in a geriatric population here may face challenges. The literacy in the geriatric population for self-rated instruments, the translation issues (semantic versus conceptual translation), population scores and cutoffs, and need for adaptation of certain items may lead to difficulties of application of the scales and interpretations of the results. Hence, there is a need for validated scales in different non-English speaking contexts as well for application in the geriatric population. These scales can be of use for not only screening for substance use disorders but also for gauging the outcomes.

Some limitations of the present review should be mentioned. Rather than a quantitative systematic review, we have a qualitative review synthesis. Hence, some relevant articles may have been missed. We do not provide summary quantitative synthesis (meta-analysis) in this review. In addition, we have not presented the quality assessment of the individual studies. Despite these limitations, the present review presents the validity parameters of scales for substance use disorders that have been tested in the elderly.


  Conclusion Top


Several instruments have been used in the elderly population. A greater utilization of validated scales can be helpful in better screening of the elderly individuals with substance use disorders. Shorter scales such as AUDIT-C and CAGE are useful for screening alcohol problem in the population. Further studies can look at how the screening instruments link to further interventions. Furthermore, specific assessments to ascertain the validity of scales for benzodiazepine, opioid, or tobacco use disorders would be helpful. There is a need for further validation of such instruments in India and other countries with increasing geriatric population, as the number of validation studies from such contexts is lacking.

Acknowledgment

The present study was partly funded by a grant of the Indian Council of Medical Research.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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