Skip to main content
OpenTrials
Completed

NCT Number: NCT06353100

Chronic Pain in the General Population of Chile

The present study seeks to follow up the cohort of adults representative of Chile's urban population whose levels of chronic pain were evaluated in March 2023 (baseline) as part of the Mental Health Thermometer (MHT) study. The study consists of a 12 month follow-up telephone interview to assess parameters of chronic pain (CP) and subtypes, mental and physical health, lifestyle and adversity and work characteristics.

The study objectives are as follows:

1. Estimate the prevalence of CP and subtypes in the general population 2. Explore the association between mental health indicators, perceived work stress and presence of CP in the population. 3. Investigate the impact of CP (functional, occupational and social) among the subset of participants reporting CP 4. Describe the use of management strategies in those who suffer from CP.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Chronic Pain Anxiety Disorders Behavior Behavioral Symptoms Depression Depression, Anxiety Dyssomnias Fibromyalgia Insomnia Loneliness Mental Disorders Migraine Disability Muscular Diseases Musculoskeletal Diseases Nervous System Diseases Neuralgia Neurologic Manifestations Neuromuscular Diseases Neuropathic Pain Pain Pathological Conditions, Signs and Symptoms Peripheral Nervous System Diseases Rheumatic Diseases Self Harm Self-Injurious Behavior Signs and Symptoms Sleep Disorders, Intrinsic Sleep Initiation and Maintenance Disorders Sleep Wake Disorders

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

Pontificia Universidad Catolica de Chile

Santiago, RM, 7550139, Chile

About this study

I. Aims of the study:

  • Estimate the prevalence of chronic pain (CP) and subtypes in the
  • Explore the association between mental health indicators, perceived work stress and the presence of CP in the urban population of Chile.
  • Asses the functional, occupational and social impact of CP in Chile´s urban population reporting CP.
  • Describe the use of management strategies in those who suffer from CP.

II. Design:

The design is longitudinal prospective and involves following up the same group of participants from the MHT study to monitor their mental health and CP parameters.

III. Study variables include:

3.1. Main outcome measures (instrument): Presence of chronic pain in the last 3 months, Severity of chronic pain (Chronic pain grade questionnaire; CPG), chronic pain interference in daily activities, social activities and work (CPG), depression (Patient Health Questionnaire; PHQ-9), anxiety (General Anxiety Disorder (GAD-7) 3.2. Secondary outcome measures: chronic pain management strategies, migraine disability (Migraine Disability Assessment, MIDAS), neuropathic pain (Neuropathic pain DN4 Questionnaire; DN4), fibromyalgia (Fibromyalgia Survey Questionnaire; FSQ), insomnia (Insomnia Severity Index; ISI), loneliness (3-item UCLA Loneliness Scale; R-UCLA) 3.3. Variables of interest: job-relates stress (Copenhagen Burnout Inventory; CBI), childhood adversity (Adverse childhood experiences; ACE), negative life events.

IV. Groups:

For the longitudinal analysis, participants will be classified into four groups:

  • Group 1 (no pain): participants who do not declare CP at baseline or follow-up
  • Group 2 (incident): participants who do not declare CP at baseline but declare it at follow-up.
  • Group 3 (remitted): participants who declare CP at baseline but do not declare it at follow-up.
  • Group 4 (chronic pain at follow-up): participants who declare CP at baseline and follow-up

V. Analysis plan:

5.1. Cross-sectional analysis (at follow-up)

  • Prevalence of CP will be calculated (with 95% confidence interval (CI)) for the Chilean urban population by sex, age group and employment status (aim 1).
  • Prevalences of the most common CP syndromes (i.e. migraine, fibromyalgia, neuropathic pain) with 96% CI will also be calculated.
  • In the subset of the population with CP, descriptive analyzes will be carried out (percentages, means and standard deviation) of the interference levels (aim 3) and chronic pain management strategies (aim 4) by sex, age group and employment status.
  • Calculation of Odds Ratios (ORs) with 95% CI for the main mental health variables associated with the presence of CI (i.e. symptoms of depression and anxiety) and for work variables (i.e. work-related stress), using logistic regression, adjusting for age, sex, physical health characteristics (aim 2).

5.2. Longitudinal analysis (baseline and follow-up)

  • The database will be integrated with the baseline data and based on the distribution of certain sociodemographic and health variables in the two times, an attrition analysis will be carried out to conclude on the selective loss of subjects.
  • Four groups will be created according to the pain trajectory between the two measurement points (see group section) and the proportion of new cases in the 12 months will be calculated (i.e. annual incidence).
  • The difference in the chronic pain intensity reported at the measurement points will be calculated.
  • Several multilevel models will be analyzed to examine the relationship between mental health (PHQ-9 and GAD- 7), sleep difficulties (ISI), perception of loneliness (UCLA-R), health variables (alcohol consumption, tobacco, body mass) and work variables (i.e. job satisfaction, work-related stress) and changes in the magnitude of perceived CP at 12 months, using linear and non-linear mixed effects models (aim 3).

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • General population
  • Residence in urban areas

Treatment and study plan

Primary outcomes

  1. Chronic pain (past 3 months)

    Time frame: Baseline and 12-month follow-up

    Participants will be asked "Have you had constant or frequent pain [most of the day] during the past 3 months?" and asked to identify the average and maximum intensity of pain in that period using a visual analogue scale (VAS) from 0 to 10. Only participants with an average pain of 4 or more will be classified as having significant chronic pain.

  2. Depression (2 weeks)

    Time frame: Baseline and 12-month follow-up

    As measured by the Patient Health Questionnaire (PHQ-9). Total scores on the PHQ-9 range from 0 to 27 and higher scores indicate higher symptoms of depression.

  3. Anxiety (2 weeks)

    Time frame: Baseline and 12-month follow-up

    As measured by the General Anxiety Disorder (GAD-7). Total scores on the GAD-7 range from 0 to 21 and higher scores indicate higher symptoms of anxiety.

Secondary outcomes

  1. Migraine Disability

    Time frame: 12-month follow-up

    As measured by the MIDAS (Migraine Disability Assessment). Total scores on the MIDAS range from 0 to 20 and higher scores indicate higher disability.

  2. Neuropathic Pain

    Time frame: Baseline and 12-month follow-up

    As measured by the DN4 (Neuropathic pain DN4 Questionnaire). Total scores on the DN4 range from 0 to 10 and Scores ≥ 4/10 indicate neuropathic pain.

  3. Fibromyalgia

    Time frame: 12-month follow-up

    As measured by the Fibromyalgia Survey Questionnaire (FSQ). The possible score ranges from 0 to 31 points. A score equal to or greater than 13 points is consistent with a diagnosis of fibromyalgia.

  4. Self harm (2 weeks)

    Time frame: Baseline and 12-month follow-up

    As measured by item 9 (Thoughts that you would be better off dead or of hurting yourself in some way) of the Patient Health Questionnaire (PHQ-9).

  5. Insomnia (2 weeks)

    Time frame: Baseline and 12-month follow-up

    As measured by the Insomnia Severity Index (ISI). Responses can range from 0 to 4, where higher scores indicate more acute symptoms of insomnia.

  6. Loneliness

    Time frame: Baseline and 12-month follow-up

    As measured by the 3-item University of California, Los Angeles Loneliness Scale (R-UCLA). Total scores range from 3 to 9 and higher scores indicate higher perceived loneliness.

Sponsors and collaborators

Lead sponsor

Pontificia Universidad Catolica de Chile

Other

Collaborators

  • Chilean Safety Association (ACHS)

Registry information

Official study title

Chronic Pain in the General Population of Chile: Longitudinal Study

Acronym: RDC

Important dates

Study start
2023
Primary completion
2025
Study completion
2025
First posted
Apr 8, 2024
Registry last updated
Dec 12, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.