Validity of international classification of functioning, disability, and health core set in patients with Parkinson's disease and the correlation with other Parkinson scales

İbrahim Acir; Hacı Ali Erdoğan; Vildan Yayla

doi:10.4103/NSN.NSN_16_20

ORIGINAL ARTICLE

Year : 2020 | Volume : 37 | Issue : 2 | Page : 89-93

Validity of international classification of functioning, disability, and health core set in patients with Parkinson's disease and the correlation with other Parkinson scales

İbrahim Acir¹, Hacı Ali Erdoğan², Vildan Yayla²
¹ Neurology Clinic, Kilis Public Hospital, Kilis Merkez, Turkey
² Neurology Clinic, Bakırköy Dr. Sadi Konuk Training and Research Hospital, Istanbul, Turkey

Date of Submission	25-May-2019
Date of Decision	08-Nov-2019
Date of Acceptance	16-Nov-2019
Date of Web Publication	29-Jun-2020

Correspondence Address:
İbrahim Acir
Neurology Clinic, Kilis Public Hospital, Kilis Merkez
Turkey

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/NSN.NSN_16_20

Abstract

Objectives: Idiopathic Parkinson's Disease (IPD) is a movement disorder that cause tremor, rigidity, bradykinesia, postural instability and deterioration quality of life. To assess the disease different scales can be used: The Unified Parkinson's Disease Rating Scale (UPDRS) for clinical severity, Parkinson's Disease Questionnaire (PDQ39) to assess quality of life, Beck Depression Scale (BD) for mood assessment and Hoehn Yahr Scale (HY) for clinical staging. The International Classification of Functioning, Disability and Health (ICF) is a classification to develop an international common language for the evaluation of the functionality and disability of patients. We aimed to compare validity and efficacy of ICF classification with other scales. Materials and Methods: Thirty-one patients with idiopathic Parkinson's disease were evaluated. PDQ39, UPDRS, Hoehn Yahr, Beck Depression Scale and 'Brief ICF core set for hand condition' which was recommended for Parkinson's disease were applied to patients. The brief ICF core set and other scales were compared and assessed if there was any correlation. For analyzes, the MedCalc Statistical Software version 12.7.7 programme was used. Results: The mean age of the IPD patients was 68.3 ± 6.9 years and 71% of them were female (22) and 29% were male (9). According to ICF codes, patients who have eight or more corrupted codes were recorded as 'major code impairment patients', and those with less than eight codes recorded as 'minor code impairment patients'. The total UPDRS score of major code impairment patients was 58.4 ± 29.8, while the mean score of minor code impairment patients was 21.2 ± 14.05. The PDQ39 score of major code impairment patients was 66.4 ± 24.1, while the mean score of minor code impairment patients was 19.3 ± 13.5. According to Hoehn Yahr stage, the ratio of stage 1 were higher in minor ICF patients. Conclusion: While assessing the functioning of the Parkinson's disease patients, we need comprehensive scales that include many parameters. The ICF coding system is an international system, which is very important to develop a common language. The significant correlation between ICF coding system and other scales in our Parkinson's patients, shows the validity of the coding system.

Keywords: International classification of functioning, disability, and health, parkinson's, quality of life scale

How to cite this article:
Acir &, Erdoğan HA, Yayla V. Validity of international classification of functioning, disability, and health core set in patients with Parkinson's disease and the correlation with other Parkinson scales. Neurol Sci Neurophysiol 2020;37:89-93

How to cite this URL:
Acir &, Erdoğan HA, Yayla V. Validity of international classification of functioning, disability, and health core set in patients with Parkinson's disease and the correlation with other Parkinson scales. Neurol Sci Neurophysiol [serial online] 2020 [cited 2023 Jun 10];37:89-93. Available from: http://www.nsnjournal.org/text.asp?2020/37/2/89/288417

Introduction

Idiopathic Parkinson's disease which is the most common movement disorder after essential tremor is a progressive neurodegenerative disease. The prevalence is 1% over the age of 60.^[1] Motor and nonmotor findings occur in intermittent peritoneal dialysis (IPD) and cause disability and deterioration in quality of life. Therefore, the scales that evaluate the quality of life in Parkinson's disease are important. The 39-item Parkinson's Disease Questionnaire (PDQ-39) which was developed in 1995 by Peto et al. The degree of clinical severity in Parkinson's disease is determined by the Unified Parkinson's Disease Rating Scale (UPDRS). UPDRS evaluates patients in terms of clinical characteristics: mentation, behavior, and mood (16 points), activities of daily living (52 points), motor examination (92 points), and complications of therapy (23 points).^[2] Hoehn–Yahr (HY) staging is consistent with the clinical severity of the patients. Although this staging is a commonly used clinical rating scale, there are some limitations such as lack of details and not including nonmotor findings. Patients are evaluated in seven stages.

The International Classification of Functioning, Disability and Health (ICF) is a multifaceted classification system, consisting of approximately 1500 categories that all countries of the world unanimously acknowledged in the World Health Organization in 2001.. ICF Core Sets have been developed because it is not practical to use all 1500 categories of ICF in clinical practice and research. ICF Core Sets are usually compatible with the ICF category list and specific to a disease or health-related situation. There are “Brief ICF Core Set” for use in clinical research and health statistics and “Comprehensive ICF Core Set” for multidisciplinary studies. Core Sets contain as little as possible the required amount of ICF categories to identify problems of individual functions in health and health-related situations.^[3] In Parkinson's disease, “ICF Core Set for Hand Conditions” can be used. The codes and categories in this set are as follows:

The aim of this study is to evaluate the validity of the ICF classification in Parkinson's patients and its relationship with other Parkinson's life quality scales.

Materials and Methods

In this study, 31 patients with idiopathic Parkinson's disease who followed up in the Bakırköy Dr. Sadi Konuk Training and Research Hospital Neurology Clinic were prospectively evaluated. The following exclusion criteria were used in patient selection:

Patients excluded from the study

Patients under 18 years
Pregnant women
Patients who are at the stage of diagnosis
Patients not receiving treatment
Patients with exclusion criteria positive for IPD.
Determination of a specific disease that may cause Parkinson's disease such as stroke, head trauma, encephalitis, neuroleptic drug use, hydrocephalus, and brain tumor

Oculogyric crisis
Supranuclear palsy
Cerebellar signs
Early severe dementia.

A consent form was obtained from all patients. Anamnesis, neurological examination findings, duration of IPD diagnosis, and additional systemic diseases were recorded. UPDRS, Beck Depression Scale, PDQ-39, Modified HY Scale, and Brief ICF Hand Condition Core Set were applied to the patients. This study was approved by the Bakırköy Dr. Sadi Konuk Training and Research Hospital Ethics Committee with the decision number 2017/123 on June 19, 2017.

Statistical analysis

In the study, 22 (71%) patients were male and 9 (29%) patients were female. The age range was 55–82 years, and the mean age was 68.3 ± 6.9 years. The duration of disease was between 1 and 10 years. The mean disease duration was 4.39 ± 2.4 years. While 11 patients had no additional disease, 4 patients had diabetes mellitus and 7 patients had hypertension. According to ICF codes, patients who have eight or more corrupted codes were recorded as “major code impairment patients” and those with <8 codes recorded as “minor code impairment patients.” Every patient had at least one corrupted code, and the highest number of corrupted codes was 21 (mean 8.25 ± 0.56). In the “minor code impairment patients” group, there were 10 male and 7 female patients. The mean age was 69.4 ± 5.9 years, and the mean duration of Parkinson's disease was 4.41 ± 2.4 years. In the “major code impairment patients” group, there were 12 male and 2 female patients. The mean age was 67 ± 8.1 years, and the mean duration of Parkinson's disease was 4.36 ± 2.5 years. There was no statistically significant difference between the two groups (P > 0.05) [Table 1].

Table 1: Comparison of age and disease duration by the International Classification of Functioning, Disability, and Health

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When the ICF codes and UPDRS scores were compared, all UPDRS scores of “minor code impairment patients” group were lower than 48 (17 patients). In the “major code impairment” group, the UPDRS score of 7 patients was above 48 and 5 patients' score was <48. A significant correlation was found between ICF Core Set and UPDRS in the “minor code impairment” group (P < 0.05) [Table 2].

Table 2: Comparison of the International Classification of Functioning, Disability, and Health and the Unified Parkinson's Disease Rating Scale scores

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When the ICF codes and Beck Depression Scale scores were compared, Beck Depression scores (25.5 ± 13.2) were higher in the “major code impairment” group. The score of “minor code impairment” group was 9.2 ± 6.5, and this difference was statistically significant (P < 0.05).

When the relationship between ICF and PDQ-39 was examined, the PDQ-39 score of “major code impairment” group was 66.4 ± 24.1, while the score of “minor code impairment” group was 19.3 ± 13.5, and this difference was also statistically significant (P < 0.05).

When the relationship between total UPDRS scores and ICF codes was examined, the score of “major code impairment” group was 58.4 ± 29.8 and the score of “minor code impairment” group was 21.2 ± 14.05. The difference was also statistically significant (P < 0.05) [Table 3].

Table 3: The comparison between the International Classification of Functioning, Disability, and Health codes and 39-item Parkinson's Disease Questionnaire, Beck Depression Scale (BD), and Unified Parkinson's Disease Rating Scale

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When the patients were evaluated according to the HY staging system, seven patients were Stage 1, 5 patients were Stage 1.5, 4 patients were Stage 2, 4 patients were Stage 2.5, 6 patients were Stage 3, 4 patients were Stage 4, and 1 patient was Stage 5. The relationship between ICF codes and HY staging was examined, and all patients with Stage 1 were in the “minor code impairment” group. Statistically, there was a significant difference between ICF code disorder and HY staging [Table 4].

Table 4: The relationship between the International Classification of Functioning, Disability, and Health codes and Hoehn-Yahr staging

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When the codes were examined one by one, the most corrupted code was seen as d440 which the fine hand skills were evaluated.

Discussion

The PDQ-39 scale questions the physical, mental, and social domains of the patients except sleep and sexual life.^[4] According to a study, mobility, daily living activities, and emotional state were the most affected areas in the PDQ-39 scale.^[5] In our study, the mean PDQ-39 score of the 31 patients was calculated as 40.5. PDQ-39 scores were significantly higher in patients who have more corrupted ICF code. According to these data, it can be said that the patients who had more corrupted ICF code have a lower quality of life and functionality and also disability is higher. On the other hand, it would not be correct to say that the PDQ-39 scale which is not questioning sleep and sexual life will be sufficient to determine the patient's functionality and quality of life.

The UPDRS has parts: UPDRS I evaluates the patient's mental status and behaviors, UPDRS II evaluates daily living activities, UPDRS III evaluates motor examination, and UPDRS IV evaluates treatment complications. It is foreseen that UPDRS II, which evaluates the activities of daily living, will give more specific information about quality of life and functionality. However, in a study comparing the quality of life and UPDRS score, the highest correlation was found in UPDRS I and also the total UPDRS score was significantly correlated with the quality of life.^[6] Many studies have shown that the UPDRS score correlates with the other quality of life scales (Parkinson's Disease Quality-of-Life Questionnaire).^[7] In our study, the UPDRS total scores were higher in patients who had more corrupted ICF code. This good correlation may be due to common items in the ICF codes and UPDRS evaluating eating, drinking, dressing, and fine hand skills.

According to the study of Dauwerse et al., quality of life is affected by health, personal relationships, care, and communication.^[8] Some studies point out that anxiety and fatigue are associated with poor quality of life. Walking disorders and drug-related motor complications were found as motor symptoms that affect the quality of life.^[9] In another study, the second most important factor affecting the quality of life was found as HY staging.^[10] Motor findings, necessity of help, and postural abnormalities are major points for evaluating the quality of life in HY staging. If we consider the necessity of help is associated with more corrupted ICF code, a good correlation with HY staging can be estimated. In our study, all seven patients with Stage 1 according to HY staging was in the “minor code impairment” group, which implies that a lower stage is associated with less corrupted ICF code. This may also be explained by similar factors which are found both in this staging system and the ICF classification.

At least one ICF code was found corrupted in all of our patients. The d440 code, which evaluates fine hand skills, was the most corrupted code in 24 patients. Considering that IPD is a neurodegenerative disease with tremor which is one of the diagnostic criteria of the disease, it can be predicted that patients would have poor hand skills, and this may have a negative effect on the quality of life. In our study, defective d440 found in most of the patients supported this hypothesis.

Evaluation of the patients' Parkinson's disease according to the ICF system “Brief ICF Core Set for Hand Conditions” may be inadequate to measure all aspects of the functionality and to assess the quality of life. The weak point of the ICF coding system is failure of the evaluation of the factors that affect directly the quality of life such as walking disorder and postural disability. If the patients were evaluated with a score of UPDRS subgroups rather than the total score of UPDRS, this approach could show which UPDRS part has more impact on the quality of life. In this respect, considering subgroups of UPDRS and ICF coding system may provide more detailed information about quality of life. Another weakness of the study is that it does not allow to evaluate the effect of gender on quality of life.

A comparison of ICF codes with multiple scales is the strong side of the study. And also, patients were evaluated with the subgroups of ICF system, and this increased the sensitivity of the study.

Several scales have been developed to evaluate the quality of life, clinical severity, and staging. In the evaluation of the functionality in patients with Parkinson's disease, there is a need for a comprehensive scale including many parameters. The ICF coding system, which includes many parameters, is an international system, and it is extremely important for creating a common language. The significant correlation between these scales and the ICF coding system in our study implies the validity of ICF coding system and suggests that it can be widely used in determining the quality of life and monitoring the patients.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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