Exclusion criteria involved
uraemic encephalopathy, poisoning, uraemia, hyperkalaemia, headaches, epilepsy, stroke, cognitive, visual, speech, or hearing impairment, pain, diabetes, tumour, headache, drug abuse, hyperuricaemia, trauma
URAEMIA, CRITICALLY ILL, RENAL ANAEMIA, HEART INSUFFICIENCY, EPILEPSY, STROKE, HYPERLIPIDAEMIA, CORONARY HEART DISEASE, DISORDERS, DIABETES, SECONDARY, HYPERPHOSPHATEMIA, TUMOUR, SECONDARY HYPERPARATHYROIDISM, HYPERTENSION, HYPERURICAEMIA, DIALYSIS HEADACHE

Patients with heart insufficiency, stroke, tumour, uraemic encephalopathy, and other serious diseases;patients with a history of drug abuse, withdrawal, poisoning, trauma, or epilepsy that may be related to headaches;patients who have cognitive, visual, speech, or hearing impairment, or cannot complete the scale assessment and are critically ill, unable to cooperate, or have serious consciousness and mental disorders; andPatients who refused to fill out the questionnaire.We prepared a semi-structure questionnaire examining the presence and clinical characteristics of headaches before and during the haemodialysis program. The questionnaire consisted of three parts.Part 1: This study collected basic information, including sex, age, occupation, whether there was a dialysis headache, whether there was a previous headache, dialysis history, and comorbidities of haemodialysis patients, including hypertension, diabetes, hyperkalaemia, hyperlipidaemia, hyperphosphatemia, hyperuricaemia, secondary hyperparathyroidism, renal anaemia, uraemia, coronary heart disease, and whether there was a cause of secondary headache.Part 2: Information on headaches before dialysis were collected, including the occurrence, duration, location, quality, intensity, accompanying symptoms, improvements after rest, worsening of daily activities, and manner of relief.Part 3: Information on headaches during dialysis were collected, including dialysis history, how long after dialysis initiation the patient began to experience a headache, how much time after dialysis the patient began to experience a headache, occurrence, duration, location, quality, intensity, accompanying symptoms, improvements after rest, worsening of daily activities, and manner of relief. The intensity was assessed using a numeric rating scale, a segmented numeric version of the visual analogue scale (VAS), where patients select a whole number from 0 to 10 based on their pain intensity [Two headache experts performed extensive face-to-face physical and neurological examinations on all patients. The patients were interviewed face-to-face concerning their headache experiences during the sessions.The patients were divided into two groups: patients with headaches and control. Patients with headaches were categorized based on their temporal profile relative to dialysis: HDH and headache after haemodialysis (HAH). Patients without headaches were classified as the comparative control group.