First comprehensive tool for screening pain in Parkinson's disease: the King's Parkinson's Disease Pain Questionnaire

BACKGROUND AND PURPOSE

Pain is highly prevalent in Parkinson's disease (PD), impacting patients' ability, mood and quality of life. Detecting the presence of pain in its multiple modalities is necessary for adequate personalized management of PD. A 14-item, PD-specific, patient-based questionnaire (the King's Parkinson's Disease Pain Questionnaire, KPPQ) was designed corresponding to the rater-based KPP Scale (KPPS). The present multicentre study was aimed at testing the validity of this screening tool.

METHODS

First, a comparison between the KPPQ scores of patients and matched controls was performed. Next, convergent validity, reproducibility (test-retest) and diagnostic performance of the questionnaire were analysed.

RESULTS

Data from 300 patients and 150 controls are reported. PD patients declared significantly more pain symptoms than controls (3.96 ± 2.56 vs. 2.17 ± 1.39; P < 0.0001). The KPPQ convergent validity was high with KPPS total score (r_S  = 0.80) but weak or moderate with other pain assessments. Test-retest reliability was satisfactory with kappa values ≥0.65 except for item 5, Dyskinetic pains (κ = 0.44), and the intraclass correlation coefficient (ICC) for the KPPQ total score was 0.98. After the scores of the KPPS were adapted for screening (0, no symptom; ≥1, symptom present), a good agreement was found between the KPPQ and the KPPS (ICC = 0.88). A strong correlation (r_S  = 0.80) between the two instruments was found. The diagnostic parameters of the KPPQ were very satisfactory as a whole, with a global accuracy of 78.3%-98.3%.

CONCLUSIONS

These results suggest that the KPPQ is a useful, reliable and valid screening instrument for pain in PD to advance patient-related outcomes.

Tauopathies with parkinsonism: clinical spectrum, neuropathologic basis, biological markers, and treatment options

Tauopathies with parkinsonism represent a spectrum of disease entities unified by the pathologic accumulation of hyperphosphorylated tau protein fragments within the central nervous system. These pathologic characteristics suggest shared pathogenetic pathways and possible molecular targets for disease-modifying therapeutic interventions. Natural history studies, for instance, in progressive supranuclear palsy, frontotemporal dementia with parkinsonism linked to chromosome 17, corticobasal degeneration, and Niemann-Pick disease type C as well as in amyotrophic lateral sclerosis/Parkinson-dementia complex permit clinical characterization of the disease phenotypes and are crucial to the development and validation of biological markers for differential diagnostics and disease monitoring, for example, by use of neuroimaging or proteomic approaches. The wide pathologic and clinical spectrum of the tauopathies with parkinsonism is reviewed in this article, and perspectives on future advances in the understanding of the pathogenesis are given, together with potential therapeutic strategies.

Tauopathies with parkinsonism: clinical spectrum, neuropathologic basis, biological markers, and treatment options

Tauopathies with parkinsonism represent a spectrum of disease entities unified by the pathologic accumulation of hyperphosphorylated tau protein fragments within the central nervous system. These pathologic characteristics suggest shared pathogenetic pathways and possible molecular targets for disease-modifying therapeutic interventions. Natural history studies, for instance, in progressive supranuclear palsy, frontotemporal dementia with parkinsonism linked to chromosome 17, corticobasal degeneration, and Niemann-Pick disease type C as well as in amyotrophic lateral sclerosis/Parkinson-dementia complex permit clinical characterization of the disease phenotypes and are crucial to the development and validation of biological markers for differential diagnostics and disease monitoring, for example, by use of neuroimaging or proteomic approaches. The wide pathologic and clinical spectrum of the tauopathies with parkinsonism is reviewed in this article, and perspectives on future advances in the understanding of the pathogenesis are given, together with potential therapeutic strategies.

Rapid onset of pergolide-induced pulmonary fibrosis in a patient with corticobasal degeneration

A 66-year-old man presented with gradually increasing dyspnoea and reduced exercise tolerance. There was no chest pain or any other respiratory symptoms, he had never smoked and there was no occupational exposure to dusts, toxins or asbestos. He also complained of a dull pain and numbness in his left forearm, unrelated to exertion.

Previous medical history included ischaemic heart disease and parkinsonism which was unresponsive to escalating therapy. Medication on presentation included aspirin 75 mg, pergolide 1 mg three times daily and two Sinemet plus three times daily.

He was apyrexial and tachypnoeic (respiratory rate 32/min), oxygen saturation 89% on air, the peak expiratory flow rate was 140 litre/min, heart rate 82 beats/minute and bloot pressure 143/66 mmHg. The jugular venous pressure was not raised and there was poor lung expansion with florid, bibasal, late inspiratory crackles to the midzones. He was bradykinetic with a marked coarse, jerky resting tremor in the left upper limb with quasi-purposeful involuntary movements and marked apraxia. There was greatly increased axial tone. No limb weakness was demonstrated, reflexes were unremarkable and the plantar response was flexor. There was sensory impairment in the left arm and leg to all modalities. His gait was bradykinetic and shuffling with retropulsion on stopping. He had a full range of eye movements with unrestricted vertical gaze.

Full blood count, urea and electrolytes, liver function tests, calcium and creatine kinase were all normal. His C-reactive protein level was 63 mg/litre and erythrocyte sedimentation rate was 45mm/hr. Arterial blood gas analysis on air revealed; partial pressure of arterial oxygen (PaO2) 7.2 Kpa, partial pressure of arterial carbon dioxide (PaCO2) 2.6 Kpa, pH 7.52, base excess 2, bicarbonate 26 mmol. An electrocardiogram showed sinus rhythm with Q waves in III and aVf.

Chest X-ray showed bilateral extensive subpleural interstitial changes and honeycombing with loss of volume particularly in the right lung (Figure 1). High resolution computed tomography of the thorax demonstrated widespread bilateral reticular shadowing suggestive of fibrosis, honeycomb changes and associated basilar traction bronchiectasis. Lung function tests demonstrated a forced expiratory volume in 1 second (FEV1) 1.41 litres (52% of predicted), forced vital capacity (FVC) 1.45 litres (43% of predicted), FEV1/FVC 97% and gas transfer factor (DLCO) 17.4 (70% of predicted).

He was treated with oxygen and antibiotics. Transbronchial biopsy with histology demonstrated diffuse fibrous tissue, with no evidence of infection, tuberculosis or malignancy. Bronchoalveolar lavage revealed a neutrophilia. Microbiology cultures were negative. His antinuclear antibody, complement levels, classical antineutrophil cytoplasmic antibody, rheumatoid factors, Scl-70 and Jo-1 antibodies were normal. Reviewing his medication with pharmacy led to the discontinuation of pergolide since it has been reported to cause diffuse interstitial pulmonary fibrosis. A consultant neurological review was sought and a diagnosis of corticobasal degeneration made.

He was discharged on home oxygen. After 1 month of discontinuing pergolide, the patient subjectively noticed improvement in his dyspnoea, reflected in an increase in DLCO (82% predicted).