Daily variation in SBP (black circles) and DBP (grey circles) over a 3 year period, as related to (1) maximum daily environmental temperatures (small black squares) and (2) periodic treatments at constant dosage with losartan (red triangles), chlorothiazide (green triangles) or ramipril (blue triangles). At bottom right, the two rows of red triangles mark the initiation of a 12 year period (2003–2014) where the day-to-day dosage of losartan was varied. Renal colic in the year 2000 is marked by a large red triangle. At that time home BP measurements were usually taken 2–3 times a day—in the early morning, in the early afternoon, and in the evening. All measurements are directly plotted. Gaps indicate periods of travel when readings were discontinued. Since records of temperature values for the subject’s lakeside city (Kingston, Ontario) did not become available until 2008, values for a location 24 km north (Hartington) were employed.