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Functional Capacity, Subjective Dyspnea and Fatigue in Smokers

Relationship Between Functional Capacity and Subjective Dyspnea and Fatigue in Young Adult Smokers

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT07520981
Enrollment
103
Registered
2026-04-09
Start date
2026-04-15
Completion date
2026-08-15
Last updated
2026-08-31

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Smoking

Keywords

functional capacity, subjectice dyspnea, fatigue, young adult smoker

Brief summary

Smoking remains a significant public health problem among the young adult population. Epidemiological studies in Turkey show a steadily decreasing age of smoking initiation and a remarkably high rate of smoking among university-aged individuals. Exposure to secondhand smoke is known to have negative effects on the respiratory system, cardiovascular system, and peripheral muscle function. Impaired lung ventilation, reduced gas exchange, and insufficient oxygen transport due to smoking can lead to decreased exercise tolerance, premature fatigue, and increased perception of exertional dyspnea. These effects can manifest as a decrease in functional capacity even before the development of a clinically significant respiratory disease. Functional capacity is an important indicator reflecting an individual's ability to perform daily living activities and is frequently assessed in clinical research using submaximal exercise tests. The 6-Minute Walk Test is a widely used, valid, and reliable test for assessing cardiorespiratory endurance and overall functional status. Similarly, the 1-Minute Sit-Stand Test is recommended as a practical and applicable method for evaluating lower extremity muscle endurance and functional performance. Dyspnea is a multidimensional symptom reflecting an individual's subjective perception of respiratory discomfort and is assessed using scales such as the Modified Medical Research Council and the Borg Dyspnea Scale. The Turkish Thoracic Society's dyspnea assessment reports indicate that exertional dyspnea may increase in smokers even if respiratory function tests are within normal limits. Fatigue, on the other hand, is a significant symptom that negatively affects an individual's daily living activities and physical functionality, arising from inflammatory processes, impaired oxygenation, and decreased physical activity levels associated with smoking. The Fatigue Severity Scale is a validated and reliable scale for assessing the impact of fatigue on an individual's physical and social life. While studies in the literature examine the effects of smoking on respiratory function and exercise capacity, studies that address the relationship between functional capacity and subjective dyspnea and fatigue in young adult smokers are limited. In particular, evaluating functional test results such as the 6-Minute Walk Test and the 1-Minute Sit-Stand Test together with dyspnea and fatigue perception will contribute to the early identification of subclinical functional effects. The aim of this study is to examine the relationships between functional capacity (6-Minute Walk Test, 1-Minute Sit-Stand Test, and Timed Up and Go Test) and subjective dyspnea (Modified Medical Research Council Scale - mMRC) and fatigue level (Fatigue Severity Scale) in young adult smokers aged 18-30 years. The findings of this study are expected to draw attention to the functional effects of smoking in young adults, contribute to the development of preventive health approaches, and facilitate the planning of physiotherapy-based assessment and intervention programs.

Interventions

OTHERAssessment

In accordance with standard testing protocols, all participants will undergo the following assessments in order: Physical Activity Assessment (International Physical Activity Questionnaire), Functional Capacity Assessment (6-Minute Walk Test, 1-Minute Sit-to-Stand Test, and Timed Up and Go Test), Subjective Dyspnea Assessment (Modified Medical Research Council Dyspnea Scale), and Fatigue Severity Assessment (Fatigue Severity Scale).

Sponsors

Istinye University
Lead SponsorOTHER

Study design

Observational model
OTHER
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes

Inclusion criteria

* Being between 18 and 30 years of age. * Being actively enrolled in university. * Being a current smoker, * Having been a regular smoker for at least the last 6 months, * Having a daily cigarette consumption of ≥1 cigarette/day. * Volunteering to participate in the study and providing written informed consent. * Having the cognitive and physical capacity to understand and complete the tests to be administered.

Exclusion criteria

* Having a diagnosed chronic respiratory disease (asthma, COPD, bronchiectasis, interstitial lung disease, etc.), * Having had an upper or lower respiratory tract infection within the last 4 weeks. Having a diagnosed heart disease (coronary artery disease, heart failure, arrhythmia, etc.), * Having a history of uncontrolled hypertension. * Having orthopedic problems affecting walking, sitting/standing, or balance, * Having a history of lower extremity surgery or serious injury within the last 6 months. * Having a history of neurological disease affecting balance, coordination, or motor control (stroke, multiple sclerosis, epilepsy, etc.). * Having a systemic disease that may prevent participation in exercise (uncontrolled diabetes, severe anemia, etc.), * Being pregnant or within the first 6 months postpartum. * Having conditions that may endanger the participant's safety during functional tests, o Refusal to complete the tests or inability to cooperate during the evaluation.

Design outcomes

Primary

MeasureTime frameDescription
6-Minute Walk Test4 weeksParticipants will be asked to walk the longest possible distance in a straight corridor for 6 minutes. At the end of the test, the total walking distance will be recorded in meters. The test will be administered according to the standard protocol recommended by the American Thoracic Society.
1-Minute Sit-Stand Test4 weeksParticipants will be recorded on the number of times they stand up completely from a chair and sit down again within 60 seconds without using their arms. This test is a valid and reliable method for evaluating lower extremity muscle endurance and functional performance.
Timed Up and Go Test4 weeksParticipants will be asked to stand up from a chair, walk 3 meters, turn around, return to the starting point, and sit back down in the chair; the test duration will be recorded in seconds. The Timed Up and Go test is a widely used, valid, and reliable test for evaluating functional mobility, balance, and gait performance.
Subjective Dyspnea Assessment4 weeksParticipants' perception of dyspnea will be assessed using the Modified Medical Research Council Dyspnea Scale. The Modified Medical Research Council scale ranges from 0 to 4, with higher scores indicating greater perceived dyspnea severity. This scale is widely used to evaluate the level of dyspnea experienced during activities of daily living.
Fatigue Assessment4 weeksFatigue level will be assessed using the Fatigue Severity Scale. The Fatigue Severity Scale consists of 9 items, each scored on a scale from 1 to 7, and the final score is calculated as the mean of all items (range: 1-7). Higher scores indicate greater fatigue severity, and a mean score of ≥4 is considered clinically significant fatigue. The Turkish version of the FSS has been shown to be valid and reliable.

Secondary

MeasureTime frameDescription
Physical Activity Level4 weeksParticipants' physical activity level will be assessed using the International Physical Activity Questionnaire - Short Form. Data will be expressed as MET-minutes/week, where higher values indicate higher levels of physical activity. Based on International Physical Activity Questionnaire - Short Form scoring guidelines, participants will be classified into low, moderate, and high physical activity levels.

Countries

Turkey (Türkiye)

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Sep 1, 2026