Claimant seeks review of an order of the Workers’ Compensation Board affirming the referee and denying claimant’s aggravation claim.
Claimant suffered a compensable back and bilateral leg injury in April, 1977. In March, 1980, he received an award of 50 percent unscheduled permanent disability for his back, 30 percent scheduled permanent disability for his right leg and 15 percent scheduled permanent disability for his left leg. In April, 1981, he received temporary disability compensation for a protruded disc, which was surgically repaired in July, 1980. In April, 1982, his right leg disability award was increased to 50 percent. In November, 1982, March and November, 1983, and April, 1984, he experienced symptomatic flare-ups of his back and leg symptoms, which resulted in periods of total disability totalling at least 60 days.
In May, 1984, claimant raised multiple issues regarding aggravation claims, and on August 23, 1984, the parties stipulated to a settlement on these terms:
“1. Since the last award or arrangement of compensation on his April 1977 claim, claimant has suffered a worsened compensable condition which became medically stationary before this hearing, and he shall be paid, for increased permanent disability in his right leg, an additional award of compensation equal to 15 degrees, 10 percent of the maximum for loss of use and function of a leg, thereby increasing the scheduled award for claimant’s right-leg disability to a total of 60 percent of the maximum.
* * * *
“3. As a disputed-claim settlement of any and all other aggravation claims which have been or may be alleged for any time up to the date of this hearing, SAIF agrees to pay claimant the total amount of $500.”
After the settlement, claimant experienced another symptomatic flare-up of his back condition in January, 1985, and filed this claim for aggravation of his 1977 injury. SAIF denied the claim, and the referee upheld the denial. On review, the Board affirmed the referee and made these findings of ultimate fact regarding claimant’s mid-back symptoms:
“Claimant’s alleged aggravation in 1985 resulted in a *690symptomatic exacerbation, rather than a pathological exacerbation, of his mid back condition. That mid back exacerbation rendered him less able to work than at the time of the August 1984 Stipulated Order. That stipulation contemplated future periods of waxing and waning mid back symptoms resulting in periods of temporary total disability. The additional diminished earning capacity claimant experienced as a result of the mid back exacerbation did not exceed that contemplated by the August 1984 Stipulated Order in either degree or duration. Claimant’s mid back exacerbation in 1985 did not result in total disability for more than 14 consecutive days.”
The Board assumed that the parties had considered medical documentation of the earlier symptomatic back flareups and that, in the light of those flare-ups, future exacerbations were anticipated. It concluded, therefore, that the 1984 stipulation contemplated future periods of increased back symptoms accompanied by diminished earning capacity. The Board then concluded that claimant had not met his burden of proving that his back condition exacerbation and the resulting loss of earning capacity were greater than anticipated. We review for errors of law and for substantial evidence on factual issues. ORS 656.298(6); ORS 183.482(7), (8).
An aggravation claim must be based on worsened conditions since the last award or arrangement of compensation. ORS 656.273(1). A worsened condition occurs when the claimant’s physical condition or symptoms become exacerbated and cause increased disability or diminished earning capacity. Perry v. SAIF, 307 Or 654, 657, 772 P2d 418 (1989). If the last award or arrangement of compensation included consideration of anticipated future exacerbations of the condition or symptoms, the claimant must prove that the worsening has been greater than was anticipated. Gwynn v. SAIF, 304 Or 345, 352-53, 745 P2d 775 (1987). Since Gwynn, we have said repeatedly that, if there was medical evidence of the possibility of future flare-ups, the assumption is that the parties considered that evidence, unless there are indications to the contrary. International Paper Co. v. Turner, 91 Or App 91, 754 P2d 589, rev den 307 Or 101 (1988); Gwynn v. SAIF, 91 Or App 84, 754 P2d 586 (1988); Mathis v. Modoc Lumber Company, 91 Or App 67, 754 P2d 590, rev den 306 Or 195 (1988).
There was no substantial evidence to support the *691Board’s finding that the parties contemplated future flare-ups in reaching their settlement. Although several flare-ups had occurred before August, 1984, the stipulated order made no reference to the prognosis for claimant’s back condition and made no additional award for that condition. Furthermore, until 1985, the record is clear that no doctor had predicted future or chronic flare-ups of the back condition. Obviously, the 1985 medical evidence regarding the possibility of future flare-ups was not available when the parties agreed to the stipulated order in 1984. Therefore, we remand to the Board for reconsideration in light of this determination.
Reversed and remanded for reconsideration.