Department of Epidemiology,Columbia University,New York,NY,USA.
Department of Psychology,University of Washington,Seattle,Washington,USA.
Psychol Med. 2019 Apr;49(6):952-961. doi: 10.1017/S0033291718001605. Epub 2018 Jul 12.
Most research on the prevalence, distribution, and psychiatric comorbidity of intellectual disability (ID) relies on clinical samples, limiting the generalizability and utility of ID assessment in a legal context. This study assessed ID prevalence in a population-representative sample of US adolescents and examined associations of ID with socio-demographic factors and mental disorders.
Data were drawn from the National Comorbidity Survey Adolescent Supplement (N = 6256). ID was defined as: (1) IQ ⩽ 76, measured using the Kaufman Brief Intelligence Test; (2) an adaptive behavior score ⩽76, and (3) age of onset ⩽18 measured using a validated scale. The Composite International Diagnostic Interview assessed 15 lifetime mental disorders. The Sheehan disability scale assessed disorder severity. We used logistic regression models to estimate differences in lifetime disorders for adolescents with and without ID.
ID prevalence was 3.2%. Among adolescents with ID, 65.1% met lifetime criteria for a mental disorder. ID status was associated with specific phobia, agoraphobia, and bipolar disorder, but not behavior disorders after adjustment for socio-demographics. Adolescents with ID and mental disorders were significantly more likely to exhibit severe impairment than those without ID.
These findings highlight how sample selection and overlap between ID and psychopathology symptoms might bias understanding of the mental health consequences of ID. For example, associations between ID and behavior disorders widely reported in clinical samples were not observed in a population-representative sample after adjustment for socio-demographic confounders. Valid assessment and understanding of these constructs may prove influential in the legal system by influencing treatment referrals and capital punishment decisions.General Scientific SummaryCurrent definitions of intellectual disability (ID) are based on three criteria: formal designation of low intelligence through artificial problem-solving tasks, impairment in one's ability to function in his/her social environment, and early age of onset. In a national population sample of adolescents, the majority of those with ID met criteria for a lifetime mental disorder. Phobias and bipolar disorder, but not behavior disorders, were elevated in adolescents with ID. Findings highlight the need to consider how behavioral problems are conceptualized and classified in people with ID.
大多数关于智力障碍（ID）的患病率、分布和精神共病的研究都依赖于临床样本，这限制了 ID 评估在法律背景下的普遍性和实用性。本研究评估了美国青少年人群代表性样本中的 ID 患病率，并研究了 ID 与社会人口因素和精神障碍之间的关联。
数据来自国家共病调查青少年补充调查（N=6256）。ID 定义为：（1）智商⩽76，使用考夫曼简明智力量表测量；（2）适应行为评分⩽76；（3）发病年龄⩽18，使用经过验证的量表测量。复合国际诊断访谈评估了 15 种终生精神障碍。希恩残疾量表评估了疾病严重程度。我们使用逻辑回归模型估计了有和无 ID 的青少年在终生障碍方面的差异。
ID 患病率为 3.2%。在 ID 青少年中，65.1%符合终生精神障碍标准。在调整社会人口因素后，ID 状态与特定恐惧症、广场恐惧症和双相情感障碍相关，但与行为障碍无关。患有 ID 和精神障碍的青少年比没有 ID 的青少年更有可能表现出严重的障碍。
这些发现强调了样本选择和 ID 与精神病理学症状之间的重叠如何可能影响对 ID 精神健康后果的理解。例如，在调整社会人口学混杂因素后，在人群代表性样本中，ID 与行为障碍之间的广泛报告的关联并未观察到。对这些结构的有效评估和理解可能通过影响治疗转介和死刑决定，对法律系统产生影响。
目前的智力障碍 (ID) 定义基于三个标准：通过人工解决问题的任务正式指定智力低下、在其社会环境中的功能受损以及早期发病年龄。在一个全国性的青少年人口样本中，大多数 ID 患者符合终生精神障碍的标准。在 ID 青少年中，恐惧症和双相情感障碍，但不是行为障碍，发病率较高。研究结果强调了需要考虑在 ID 人群中如何对行为问题进行概念化和分类。
