How does the "body clock" affects symptoms of illness?
Among the various biologic rhythm cycles that medical chronobiologists study,
the 24-hour day/night-activity/rest cycle is considered a key chronobiologic factor in medical diagnosis and treatment. Formally known as
the circadian rhythm, it's also referred to as the "body clock."
Why is the 24-hour body clock so important?
Because so many of our normal
body functions follow daily patterns of speeding up and slowing down, intensifying and diminishing, in alignment with circadian rhythm.
Interestingly, so do the symptoms of a number of chronic disorders:
Allergic rhinitis: (nasal inflammation associated with
hay fever) Symptoms of sneezing, runny nose, and stuffy nose are typically worse in the early waking hours than later during the day.
Asthma: In most patients, symptoms are more than 100 times as likely to
occur in the few hours prior to awakening than during the day.
Stable angina: Chest pain and
electrocardiographic (ECG,
EKG) abnormalities are
most common during the first 4 to 6 hours after awakening.
Prinzmetal's angina: ECG abnormalities are most common
during sleep; chest pain can occur even while at rest.
Heart attack: Heart attack most commonly occurs in the early waking hours.
Stroke: Strokes most commonly occur in the early waking hours.
Hypertension: The highest blood pressure readings typically occur from late
morning to middle afternoon; lowest occur during early sleep. Therapy now exists that works with your body clock; consult your physician
about this treatment. Clinical studies are underway to further this research.
Rheumatoid arthritis:
RA symptoms are most intense upon awakening.
Osteoarthritis: Symptoms
of osteoarthritis worsen in the afternoon and evening.
Ulcer disease: The pain typically occurs after stomach
emptying, following
daytime meals, and in the very early morning, disrupting sleep.
Epilepsy: Seizures often occur only at particular times of the day or night;
individual patterns differ among patients.