Interstitial Lung Disease (ILD) is an umbrella term used for a large group of diseases that cause scarring (fibrosis) of the lungs. The scarring causes stiffness in the lungs which makes it difficult to breathe and get oxygen to the bloodstream. Lung damage from ILDs is often irreversible and gets worse over time [1].

The most common symptom of all ILDs is shortness of breath at rest or aggravated by exertion. This is often accompanied by a dry cough, chest discomfort, fatigue and occasionally weight loss [1,2].

The clinical presentation of many ILDs is insidious; however, they may also present acutely. In some instances patients need to be hospitalized during the first manifestation of what ultimately proves to be a chronic ILD. Examples of ILDs that usually require hospitalization include acute exacerbations of Idiopathic Pulmonary Fibrosis (AE-IPF), Acute Interstitial Pneumonia (AIP), Cryptogenic Organizing Pneumonia (COP), Acute Eosinophilic Pneumonia (AEP), rapidly progressive or acute exacerbation of connective tissue disease-associated ILDs (CTD-ILD) and drug-induced ILDs [3].

There is paucity of studies on the Clinical characteristics of patients diagnosed with Interstitial Lung Diseases (ILD), in this hilly area of northern India. The present study was done to evaluate the Clinical characteristics of Interstitial Lung Diseases (ILDs) patients.

Aims and Objectives

To study the Clinical characteristics of Interstitial Lung Diseases (ILDs) patients.

The present study was conducted at Indira Gandhi Medical College, Shimla which is a tertiary care center of Himachal Pradesh, located in North India in Asian Continent and covers the majority of the population of this state. All consecutive patients of Interstitial Lung Diseases (ILDs), attending the outpatient services of the Department of Pulmonary Medicine, IGMC Shimla from July 2018 to June 2019 were screened for enrolment in the study. All types of ILDs were enrolled in the study.

Inclusion Criteria

• Stable ILD Patients: Diagnosis of ILD according to ATS/ERS guidelines based on an overall assessment of High-Resolution Computed Tomography (HRCT) scan, lung function tests, (bronchoscopy and biopsy, if available)

• Age >18 years, written consent

Exclusion Criteria

• Subjects with evidence of left heart disease, Chronic kidney disease, Liver disease

• Chronic lung diseases other than ILDs

• Patients with HIV

• Pregnant

Patients presenting with respiratory symptoms such as cough, shortness of breath and diagnosed cases of ILD were evaluated.

All consecutive ILD patients were subjected to focused history and physical examination as structured questionnaire record information related to; Demographics, Duration of ILD, Clinical characteristics etc.

The data was collected, entered in the MS Excel sheet and analyzed using Epi info V7 software. Continuous variables were reported as mean ± SD or median and interquartile range depending on the distribution of the variables. Categorical variables were recorded as counts and percentages. Differences between means of continuous variables were compared using the unpaired student’s’ test.  A p-value of <0.05 was considered as statistically significant.

Among the study population, 50 patients 27 (54%) were female and 23 (46%) were male. The mean age of the study population was 57.821+5.03years. The mean age of males and females was 62.561+3.84 years and 53.771+5.07 years respectively. The mean duration of symptoms of ILD was 3.034+2.62 years. There was no significant difference between males and females regarding the duration of illness (2.76+2.46 years versus 3.39+2.77 years, p = 0.40) (Table 1).

Cough was the predominant symptom observed in 49(98%) of the patients followed by breathlessness mMRC grade II/III in 45(90%). The exertional chest pain was reported by 17 (34%) of the patients and there was no significant difference in males 9(39.17%) and females were 8(30.47%). History of syncope was recorded in 16(32%) of patients and had no gender predilection 7(30.47%) versus 9(33.33%) p = 0.82. On examination, a total of 32 (62%) patients had clubbing of different grades. Males outnumbered females in frequency of clubbing (73.9% versus 55.4%, p = 0.17). Overall eleven (22%) patients had raised JVP with no male and female disparity 5(21.74%) versus 6(22.22%) p = 0.61.) Velcro crackle was detected on auscultation among 29 (58%) patients,  with no male-female difference (14(60.87%) versus 15(55.54) % (respectively), with a p- value of 0.46.  (Table 2).

ILD is characterized by continued deterioration with progressive respiratory insufficiency leading to end-stage fibrosis [4].

The mean age of the study population was 57.821+5.03 with male and female mean age 62.561+3.84 and 53.771+5.07 respectively.  Females were more than male and younger with a mean duration of ILD of 3.034±2.62 years. A similar finding was also reported in the study conducted by Agarwal. et al. [5]. In the ILD registry of Indian data, it was reported that ILDs occur at a younger age compared to the western countries and females are affected more [6].

Table 1: Age and Gender Distribution of the Study Population (N = 50)

Table 2: Clinical Characteristics of the Study Population (N = 50)

Note: *mMRC; Modified Medical Research Council ^**JVP; Jugular Venous Pressure

In the present study, cough and dyspnea of various grades were the main complaints seen in all patients followed by an exertional syncope and chest pain. History of syncope was recorded in 16(32%) while 32 (62%) patients had clubbing of different grades. Raised JVP and Velcro crackle on auscultation were predominant signs among ILD patients. Various studies in the literature [7-9], reported dyspnea in 59-98% of patients and figures are comparable to our study.

Most of ILD patients had cough, breathlessness mMRC grade II/III, exertional chest pain, history of syncope, clubbing, raised JVP and Velcro crackle on auscultation.

Limitations of the Study

The small number of the population were included in this study represents a methodological limitation and study over a larger population is recommended.

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