--- title: "Marital status and incident screen-positive cognitive impairment: Differences by SPMSQ versus AD8" id: "plos-one-13-marital-status-and-incident-screen-positive-cognitive-impairment-in-a-taiwanese" canonical_url: "https://medichelpline.com/clinical-feed/plos-one-13-marital-status-and-incident-screen-positive-cognitive-impairment-in-a-taiwanese" content_type: "clinical_feed_article" specialty: "Neurology" source_name: "PLOS ONE (Medicine)" source_url: "https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0359778" published_at: "2026-10-05T14:00:00.000Z" evidence_level: "Journal Feed" license: "CC-BY-NC-4.0 / Informational Use" --- # Marital status and incident screen-positive cognitive impairment: Differences by SPMSQ versus AD8 ## Provenance & Clinical Metadata - **Canonical URL:** https://medichelpline.com/clinical-feed/plos-one-13-marital-status-and-incident-screen-positive-cognitive-impairment-in-a-taiwanese - **Specialty:** [Neurology](https://medichelpline.com/clinical-feed/neurology.md) - **Primary Source:** PLOS ONE (Medicine) - **Source URL:** [Original Journal Publication](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0359778) - **Published At:** 2026-10-05T14:00:00.000Z - **Evidence Rating:** Journal Feed ## Executive GIST (TL;DR) - This longitudinal cohort study analyzed 103,863 community-dwelling adults aged ≥65 years from the Taipei City Elderly Health Examination Database spanning 2005–2016. It compared associations between baseline **marital status** and incident screen-positive cognitive impairment (MCI) across two cognitive screening periods using different instruments. - Cognitive status was measured with the performance-based **SPMSQ** from 2005–2011 (n = 61,304) and the informant-capable **AD8** from 2012–2016 (n = 42,559). Screen-positive cutoffs were SPMSQ ≥3 and AD8 ≥2. - Baseline marital categories were married (reference), divorced, widowed, and never-married; marital status was fixed at baseline for primary analyses. Covariates included age, sex, education, living arrangement, low-income status (baseline) and time-updated health, psychiatric, behavioral and BMI measures. - Cox proportional hazards models with time-updated covariates were fit separately for the SPMSQ and AD8 periods and adjusted for demographic, socioeconomic, health, and lifestyle factors. - Key contrasting findings: in the SPMSQ period, **never-married** participants had higher risk of incident MCI versus married (HR 1.37, 95% CI 1.08–1.74). In the AD8 period, never-married status was associated with lower risk (HR 0.60, 95% CI 0.46–0.77). - Effect modification by sex and age was observed across periods. Subgroup analyses and sensitivity checks (follow-up duration stratification; exclusion of early cases; time-varying marital status in AD8 period) produced consistent patterns. - Authors interpret the reversal in the never-married association as likely reflecting **measurement heterogeneity** (difference between performance-based vs. informant-report screening, follow-up duration, and population composition) rather than a confirmed temporal change in risk. - Limitations explicitly noted include potential reverse causation due to baseline marital status ascertainment, lack of information on whether AD8 was completed by informant versus self-report, incomplete mortality linkage beyond 2012, and reliance on screening instruments rather than clinical diagnoses. - Implication: associations between marital status and cognitive impairment depend on the cognitive measurement approach and study period; interpretation should consider instrument modality and possible reporting biases related to co-residence or informant availability. ## Clinical Analysis & Structured Key Points Marital status and incident screen-positive cognitive impairment in a Taiwanese longitudinal cohort (2005–2016): Associations vary by cognitive screening instrument | PLOS One Browse Subject Areas ? Click through the PLOS taxonomy to find articles in your field. For more information about PLOS Subject Areas, click here . Article Authors Metrics Comments Media Coverage Peer Review Reader Comments Figures Figures Abstract Marital status has been associated with cognitive aging; however, whether such associations vary according to cognitive assessment modality remains unclear. This study examined whether associations between marital status and incident screen-positive cognitive impairment (MCI) differ by screening instrument and population subgroups in a large longitudinal cohort of community-dwelling older adults in Taiwan. We analyzed 103,863 adults aged ≥65 years from the Taipei City Elderly Health Examination Database (2005–2016). Cognitive status was assessed using the Short Portable Mental Status Questionnaire (SPMSQ; 2005–2011) and the 8-item Ascertain Dementia questionnaire (AD8; 2012–2016). Baseline marital status was categorized as married, divorced, widowed, or never married. Cox proportional hazards models with time-updated covariates were fitted separately for each assessment period, adjusting for demographic, socioeconomic, health, and lifestyle factors. Sensitivity analyses were conducted to examine potential reverse causation and variation in follow-up duration. Among 61,304 participants assessed during the SPMSQ period, never-married individuals had a higher risk of incident MCI compared with married individuals (hazard ratio [HR] 1.37, 95% confidence interval [CI] 1.08–1.74). In contrast, among 42,559 participants assessed during the AD8 period, never-married status was associated with a lower risk of MCI (HR 0.60, 95% CI 0.46–0.77). Effect modification by sex and age was observed across periods. Sensitivity analyses yielded consistent findings. Associations between marital status and incident MCI differed across assessment periods that varied in screening instrument, follow-up duration, and population composition; this measurement heterogeneity, rather than a confirmed temporal change, may account for the reversal observed among never-married participants. These findings suggest that interpretation of marital status–cognition associations should be considered alongside the measurement approach and study period under which they were derived. Citation: Zhou Y-C, Chou Y-C, Hung Y-L, Chang Y-J (2026) Marital status and incident screen-positive cognitive impairment in a Taiwanese longitudinal cohort (2005–2016): Associations vary by cognitive screening instrument. PLoS One 21(10): e0359778. https://doi.org/10.1371/journal.pone.0359778 Editor: Muhammad Shakaib, NED University of Engineering and Technology, PAKISTAN Received: March 10, 2026; Accepted: September 17, 2026; Published: October 5, 2026 Copyright: © 2026 Zhou et al. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability: The Taipei City Elderly Health Examination Database is a government-administered public health database owned by Taipei City Hospital, a public institution. Access restrictions are imposed solely due to legal obligations under Taiwan’s Personal Data Protection Act and ethical requirements to protect participants’ privacy — not due to any competing interests or proprietary commercial considerations. Other researchers can access this database through the same process as the authors, by submitting a formal data access application to the Taipei City Hospital Research Ethics Committee (Email: hrp@tpech.gov.tw ). Funding: This study was supported by the Taipei City Hospital, Taiwan (TPCH-114-06). The funder provided access to the Taipei City Elderly Health Examination Database for this study. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist. Introduction The rising prevalence of dementia among aging populations represents a critical global health challenge, with cases projected to triple to 152 million by 2050 [ 1 – 3 ], significantly impacting quality of life and healthcare sustainability [ 4 , 5 ]. Understanding modifiable risk factors for cognitive decline has become increasingly urgent given demographic shifts toward rapidly aging populations, particularly in societies experiencing compressed aging trajectories [ 6 ]. Marital status has emerged as a potentially important protective factor against cognitive decline, with extensive research examining how marital relationships affect brain health and cognitive resilience [ 7 , 8 ]. Theoretically, the continuous mental stimulation from daily marital interactions may contribute to enhanced cognitive reserve through sustained social engagement, emotional support, and shared cognitive activities [ 9 ]. Although mild marital stress may benefit cognitive function through adaptive challenge [ 10 ], predominantly negative marital experiences are associated with increased cognitive decline risk [ 11 ]. Nevertheless, findings regarding the protective effects of marriage remain inconsistent [ 12 , 13 ]. Large epidemiological studies have identified higher rates of cognitive impairment among never-married individuals [ 14 ], yet other studies suggest that unmarried older adults may actually have a lower risk of dementia after adjusting for socioeconomic and health factors [ 12 ]. The role of biological sex further complicates these associations. Some studies indicate that marital dissolution through divorce or spousal death disproportionately increases cognitive vulnerability in men, possibly reflecting differences in social network maintenance and emotional coping strategies [ 13 , 15 ]. However, other studies have found no significant sex differences after adjusting for socioeconomic and other confounding factors [ 16 ]. A fundamental but underappreciated source of inconsistency in this literature is how cognitive impairment is operationalized and measured. Performance-based tests (e.g., Short Portable Mental Status Questionnaire, SPMSQ) directly assess cognitive abilities through structured tasks, while informant-based questionnaires (e.g., 8-item Ascertain Dementia, AD8) rely on reports of functional decline [ 17 , 18 ]. These modalities capture distinct aspects: performance-based tests measure current cognitive capacity, whereas informant-based tools detect changes from prior baseline and may better reflect functional impact. Critically, informant-based assessments may be susceptible to differential reporting bias—married individuals typically have co-residing spouses who detect subtle changes, whereas never-married individuals may rely on self-report or less frequent observers. Despite this, few studies have systematically compared marital status-cognition associations across assessment modalities within the same population. A related conceptual challenge in this literature is the possibility of reverse causality [ 15 , 19 ]. Rather than marital status causally shaping cognitive trajectories, incipient cognitive decline—even at a subclinical stage, before it would be detected on a screening instrument—may itself influence an individual’s likelihood of marrying, remaining married, or experiencing marital dissolution. Individuals with early, undetected cognitive changes may be less likely to initiate or sustain a long-term marriage, more likely to experience divorce or separation as a result of relationship strain, or, conversely, more likely to remain married if a spouse compensates for emerging functional difficulties in ways that delay formal detection. This possibility is particularly salient in observational cohorts with infrequent assessment intervals, where subclinical decline may precede the first recorded cognitive assessment by several years. Although our analytic strategy includes lag analyses intended to mitigate this concern (see Methods), the baseline ascertainment of marital status cannot fully rule out reverse causal pathways, and this conceptual limitation should be borne in mind when interpreting the associations reported below. This study addresses this gap using a large longitudinal cohort of community-dwelling older adults in Taiwan, spanning a transition between two screening instruments (SPMSQ 2005–2011 versus AD8 2012–2016). Taiwan’s rapid demographic transition (projected super-aged society by 2025) and universal healthcare system provide a unique context for examining whether marital status-cognition associations differ across measurement approaches and are modified by sex, age, education, and health status. We hypothesized meaningful heterogeneity across both measurement approaches and population strata. Findings will clarify how measurement choices influence observed associations, identify vulnerable subgroups, and inform the development of targeted cognitive health interventions for diverse older populations in rapidly aging societies. Materials and methods Study population This 11-year longitudinal prospective cohort study utilized data from the Taipei City Elderly Health Examination Database, established through collaboration between Taipei City Hospital and the Taipei City Department of Health. The database aggregates annual health examination data from multiple public and private medical institutions. The dataset covering the study period (2005–2016) was accessed for research purposes on 01/06/2025. The study population comprised adults aged ≥65 years participating in government-sponsored annual health examinations (2005‒2016), including standardized physical/oral examinations and self-administered questionnaires. Of the 184,403 individuals identified, participants were screened per predefined eligibility criteria ( Fig 1 ). Exclusion criteria included: single examination records (n = 44,254 for Short Portable Mental Status Questionnaire [SPMSQ]; n = 32,700 for 8-item Ascertain Dementia [AD8]), baseline dementia medication use (n = 399 for SPMSQ; n = 411 for AD8), and incomplete questionnaire data (n = 1,185 for SPMSQ; n = 709 for AD8). The final analysis included 103,863 participants (n = 61,304 for SPMSQ; n = 42,559 for AD8) with mean follow-up periods of 3.7 years (SPMSQ) and 2.8 years (AD8). The study was conducted in accordance with the principles of the 1964 Helsinki Declaration. The data were anonymized and encrypted prior to analysis, and the Institutional Review Board of Taipei City Hospital approved the study and granted an exemption from the requirement for written informed consent given that the data were originally collected for public health surveillance and research purposes (IRB No. TCHIRB-11303014-E). Download: PNG larger image TIFF original image Fig 1. Flow chart of the patient selection process. https://doi.org/10.1371/journal.pone.0359778.g001 Measures of cognitive function In this study, screen-positive cognitive impairment (hereafter referred to as MCI for brevity and consistency with prior literature using these instruments) was ascertained using the SPMSQ and AD8 questionnaires. As both the SPMSQ and AD8 are validated screening tools rather than clinical diagnostic instruments, the resulting classification reflects screen-positive status based on a standardized cutoff rather than a clinical diagnosis of mild cognitive impairment or dementia. The SPMSQ serves as an established cognitive assessment instrument designed for older adults [ 20 ]. It comprises ten questions that evaluate multiple cognitive domains, encompassing temporal and spatial orientation, recall abilities, general knowledge awareness, and arithmetic skills. Scoring methodology is based on the number of incorrect responses, where each wrong answer receives a score of “1” while correct answers receive a score of “0.” The resulting assessment ranges from 0–10 points. Scores between 0‒2 suggest preserved cognitive function, whereas scores ≥3 indicate MCI. The AD8 functions as a cognitive decline detection instrument comprising eight evaluation criteria [ 21 ]. Each criterion utilizes a binary scoring system: 0 represents “no observable change,” while 1 indicates “change detected.” The assessment targets functional cognitive abilities across various life domains: decision-making capacity, engagement levels, repetitive behaviors, acquisition of new information, spatial-temporal awareness, monetary management, scheduling adherence, and cognitive coherence. A cumulative AD8 score of ≥2 indicates MCI. This assessment tool offers flexibility in administration, allowing completion through either caregiver observation or individual self-evaluation; however, the database did not record which respondent type (self vs. caregiver/informant) was used for each assessment, precluding direct stratification by informant type. Both the SPMSQ and AD8 used in this study were traditional Chinese versions that have been well validated in the Taiwanese population. Measures of marital status We measured marital status at baseline using a self-reported questionnaire. This variable was treated as a fixed characteristic throughout the follow-up period and included four categories: married (reference), divorced, widowed, and never-married. Covariates Covariates were defined based on established epidemiological criteria [ 22 , 23 ]. They were categorized as either fixed baseline variables or time-dependent variables. Baseline covariates, assessed at the start of the study, included age, sex (male or female), educational attainment (<6, 7–9, or ≥10 years), low-income household status, and living arrangement (alone or with others). In Taiwan, low-income household status was defined as an average monthly disposable income per capita below 60% of the minimum subsistence level ( [!CAUTION] > MedicHelpline content is structured for research, educational, and professional discovery purposes. 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